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SSC Previous Year GK Questions with Answers

General knowledge questions asked in the official papers of SSC exams, SSC CGL, SSC CHSL, SSC MTS, SSC GD Constable and SSC CPO, in one place. Each comes with the correct answer, an explanation and the exam, year and shift it was asked in.

Pick a year below to see that year's questions, or open an exam's own page for its papers alone. Questions from one exam are often asked again in another, so revising the whole SSC family together is a quick way to cover what the papers test.

Previous Year Questions

Q301.Static GKAsked in: SSC CHSL · 19 Oct 2020, Shift 3Easy

Which country is called the 'Coffee Bowl of the World'?

  1. A.Brazil
  2. B.Mexico
  3. C.India
  4. D.Serbia
Show answer

Correct answer: A. Brazil

Explanation

The correct answer is A, Brazil. Brazil is called the Coffee Bowl of the World because it grows and sends out more coffee than any other country and has done so for more than a century. Its coffee belt lies in the south-east, in the states of Minas Gerais, Sao Paulo and Parana, where the deep red soil called terra rossa, the warm climate and the rolling plateau suit the plant. The large estates there are known as fazendas, and the port of Santos handles much of the export. Coffee needs a hot, wet climate with well drained slopes, which is why it is a plantation crop of the tropics. B is wrong because Mexico is a smaller coffee grower and is better known for maize and silver. C is wrong because India grows coffee mainly in Karnataka, Kerala and Tamil Nadu but is far behind Brazil. D is wrong because Serbia has a cool climate that cannot support coffee at all. Exam tip: Brazil Coffee Bowl of the World, Sri Lanka Pearl of the Indian Ocean, Cuba Sugar Bowl of the World.

Q302.Computer AwarenessAsked in: SSC CHSL · 14 March, 2023, Shift 2Easy

Which of the following shortcut key is used to repeat the last command or action, if possible, in MS-Excel 365?

  1. A.Ctrl + Z
  2. B.Shift + Z
  3. C.Ctrl + Y
  4. D.Shift + Y
Show answer

Correct answer: C. Ctrl + Y

Explanation

The correct answer is C, Ctrl + Y. In MS Excel 365, Ctrl + Y repeats the last command or action wherever repeating it is possible, so if you have just made a cell bold or inserted a row, pressing Ctrl + Y does the same thing again at the new position. It also works as Redo, undoing an undo, because Excel treats the two as one key. The function key F4 does the same repeat job in Excel, which is why it is popular for copying formatting down a sheet. A is wrong because Ctrl + Z is Undo, which cancels the last action instead of repeating it. B is wrong because Shift + Z is not a command shortcut in Excel; it simply types a capital Z. D is wrong because Shift + Y likewise only types a capital Y. Exam tip: Ctrl + Z undo, Ctrl + Y redo or repeat, Ctrl + C copy, Ctrl + V paste, and F4 also repeats in Excel.

Q303.General ScienceAsked in: SSC CHSL · 14 March, 2023, Shift 2Easy

In humans, the digestion of carbohydrates like starch, begins in which of the following parts?

  1. A.Rectum
  2. B.Small Intestine
  3. C.Oesophagus
  4. D.Buccal cavity
Show answer

Correct answer: D. Buccal cavity

Explanation

The correct answer is D, Buccal cavity. In humans the digestion of starch begins in the buccal cavity, that is the mouth. The salivary glands pour out about 1.5 litres of saliva a day, and the enzyme in it, salivary amylase or ptyalin, breaks starch into the simpler sugar maltose. This is why a piece of chapati or rice starts tasting slightly sweet if it is chewed for a while. The saliva also wets the food so the tongue can roll it into a bolus for swallowing. A is wrong because the rectum only stores the waste left after digestion and absorption. B is wrong because in the small intestine pancreatic amylase carries this work forward and maltase finishes it into glucose, but it does not begin there. C is wrong because the oesophagus is only a food pipe that pushes the bolus down by peristalsis and has no digestive enzyme. Exam tip: starch begins in the mouth with salivary amylase, protein in the stomach with pepsin, fat in the small intestine with lipase and bile.

Q304.Art & CultureAsked in: SSC CHSL · 14 Oct 2020, Shift 3Easy

'Avesta', also called 'Zend-Avesta', is the sacred book of:

  1. A.Zoroastrianism
  2. B.Buddhism
  3. C.Jainism
  4. D.Judaism
Show answer

Correct answer: A. Zoroastrianism

Explanation

The correct answer is A, Zoroastrianism. The Avesta, also called the Zend-Avesta, is the sacred book of the Zoroastrians, the followers of the prophet Zarathustra or Zoroaster of ancient Iran. It is written in Avestan, an old Iranian language close to the Sanskrit of the Rigveda, which is why the two texts share many words and gods. Its oldest and most respected part is the Gathas, the hymns held to be Zarathustra's own words. Zoroastrians worship Ahura Mazda, the lord of wisdom, keep a sacred fire burning in their temples and follow the rule of good thoughts, good words and good deeds. Their descendants in India are the Parsis, who reached Gujarat around the eighth century. B is wrong because the Buddhist canon is the Tripitaka, written in Pali. C is wrong because the Jain scriptures are the Agamas or Angas, in Prakrit. D is wrong because the sacred book of Judaism is the Torah, part of the Hebrew Bible. Exam tip: Avesta Zoroastrian, Tripitaka Buddhist, Agama Jain, Torah Jewish, Guru Granth Sahib Sikh.

Q305.Indian HistoryAsked in: SSC CHSL · 6 Aug 2021, Shift 1Medium

In the Battle of Swally (1612) the British fought against the ______.

  1. A.Danish
  2. B.Portuguese
  3. C.Dutch
  4. D.French
Show answer

Correct answer: B. Portuguese

Explanation

The correct answer is B, Portuguese. The Battle of Swally was fought in November 1612 off Suvali, a village near Surat on the Gujarat coast. A small English squadron under Captain Thomas Best defeated a larger Portuguese fleet, and the victory ended the belief that the Portuguese could not be beaten at sea in Indian waters. Jahangir's officers watched the fight from the shore, and soon after the English were allowed to open a factory at Surat, their first real foothold on the western coast, confirmed by an imperial farman. Sir Thomas Roe's embassy of 1615 built on this opening. A is wrong because the Danes came later, setting up at Tranquebar in 1620, and took no part in this battle. C is wrong because the Dutch fought the English elsewhere, most bitterly over the spice trade at Amboyna in 1623. D is wrong because the French East India Company was founded only in 1664. Exam tip: Swally 1612, Thomas Best beat the Portuguese, and the Surat factory followed.

Q306.Indian PolityAsked in: SSC CHSL · 16 March 2018, Shift 1Medium

74th Constitutional Amendment Act gave Constitutional recognition to municipalities by adding ________.

  1. A.Part IX-A
  2. B.Part X
  3. C.Part XI
  4. D.Part XIV
Show answer

Correct answer: A. Part IX-A

Explanation

The correct answer is A, Part IX-A. The 74th Constitutional Amendment Act, 1992 inserted a new Part IX-A titled The Municipalities into the Constitution, and it came into force on 1 June 1993. This Part runs from Article 243P to Article 243ZG and gave urban local bodies a constitutional footing for the first time. It fixed three kinds of municipality: a Nagar Panchayat for an area moving from rural to urban, a Municipal Council for a smaller urban area and a Municipal Corporation for a larger urban area. The same Act added the Twelfth Schedule, which lists 18 subjects such as urban planning, water supply, slum improvement and public health that a state may hand over to these bodies. Elections every five years, seats reserved for women and Scheduled Castes, and a State Finance Commission also came with it. B is wrong because Part X covers Scheduled and Tribal Areas. C is wrong because Part XI deals with Centre-State relations. D is wrong because Part XIV covers services under the Union and the States. Exam tip: 73rd Amendment gives Part IX and the Eleventh Schedule for panchayats, 74th gives Part IX-A and the Twelfth Schedule for municipalities.

Q307.Sports GKAsked in: SSC GD Constable · 10 Jan 2023, Shift 1Hard

Which State won the Vijay Hazare Trophy in 2017-18?

  1. A.Uttar Pradesh
  2. B.Kerala
  3. C.Maharashtra
  4. D.Karnataka
Show answer

Correct answer: D. Karnataka

Explanation

The correct answer is D, Karnataka. Karnataka won the 2017-18 Vijay Hazare Trophy, beating Saurashtra in the final played in Delhi. The tournament is India's premier domestic limited-overs competition for state teams, run by the Board of Control for Cricket in India since 2002-03, and it is named after Vijay Hazare, the batsman who led India to its first Test victory, against England at Madras in 1952. Karnataka's Mayank Agarwal was the story of that season, scoring 723 runs, the highest total by any batsman in a single edition of the trophy. Option A is wrong because Uttar Pradesh did not reach the 2017-18 final. Option B is wrong because Kerala was knocked out before the final that season. Option C is wrong because Maharashtra also failed to reach the final; Karnataka's opponent was Saurashtra. Exam tip: Vijay Hazare Trophy is the one-day tournament, the Ranji Trophy the first-class one and the Syed Mushtaq Ali Trophy the Twenty20 one.

Q308.Environment & EcologyAsked in: SSC GD Constable · 1 March 2019, Shift 1Easy

In which layer of the earth's atmosphere is the ozone layer found?

  1. A.Troposphere
  2. B.Mesosphere
  3. C.Exosphere
  4. D.Stratosphere
Show answer

Correct answer: D. Stratosphere

Explanation

The correct answer is D, Stratosphere. The ozone layer lies in the stratosphere, roughly 15 to 35 km above the ground, with the thickest concentration near 20 to 25 km, and that belt is sometimes called the ozonosphere. Ozone is a molecule of three oxygen atoms, and it forms there when ultraviolet light splits oxygen molecules and the free atoms join other oxygen molecules. It absorbs harmful ultraviolet-B radiation and so shields life from skin cancer, cataracts and crop damage, and because it takes in this energy the temperature in the stratosphere rises with height, which makes the layer stable and good for jet flight. Chlorofluorocarbons from refrigerators and aerosols destroy it, so the Montreal Protocol was signed in 1987 to phase them out, and 16 September is marked as World Ozone Day. Option A is wrong because the troposphere is the lowest layer, where all weather happens. Option B is wrong because the mesosphere lies above the stratosphere and is where meteors burn up. Option C is wrong because the exosphere is the outermost, almost airless layer. Exam tip: troposphere, stratosphere with ozone, mesosphere, thermosphere, exosphere, in that order going up.

Q309.Indian PolityAsked in: SSC GD Constable · 17 Jan 2023, Shift 4Medium

The Governor of State possesses the pardoning power under which Article of the Constitution of India?

  1. A.Article 163
  2. B.Article 161
  3. C.Article 55
  4. D.Article 145
Show answer

Correct answer: B. Article 161

Explanation

The correct answer is B, Article 161. Article 161 lets the Governor grant pardons, reprieves, respites and remissions of punishment, and suspend, remit or commute the sentence of any person convicted of an offence against a law on a matter to which the executive power of the state extends. His power is narrower than the President's under Article 72 in two ways: the Governor cannot pardon a death sentence and has no say in a sentence passed by a court martial, while the President can act in both cases. Like the President, the Governor exercises this power on the advice of the state Council of Ministers. Option A is wrong because Article 163 provides for the Council of Ministers to aid and advise the Governor. Option C is wrong because Article 55 lays down the manner of election of the President. Option D is wrong because Article 145 lets the Supreme Court frame rules of procedure. Exam tip: Article 72 for the President's pardon and Article 161 for the Governor's; only the President can pardon a death sentence or a court-martial sentence.

Q310.GeographyAsked in: SSC GD Constable · 18 Feb 2019, Shift 1Medium

In which Indian state is bamboo drip irrigation system a very old practice?

  1. A.Chattisgarh
  2. B.Meghalaya
  3. C.Telangana
  4. D.Maharashtra
Show answer

Correct answer: B. Meghalaya

Explanation

The correct answer is B, Meghalaya. Bamboo drip irrigation is a two-hundred-year-old practice of the Khasi and Jaintia hills of Meghalaya. Water from a hill spring or stream is led through split bamboo pipes, channels and diversion sections down the slope, and the flow is cut down stage by stage until the last narrow pipe drips water right at the root of the plant. Around eighteen to twenty litres a minute entering the system come out as twenty to eighty drops a minute at the plant. It is used mainly for betel leaf and black pepper grown along with areca nut, needs no pump or electricity, and is studied as a model of water harvesting on steep ground where channels cannot be dug. Option A is wrong because Chhattisgarh relies on tank and canal irrigation. Option C is wrong because Telangana depends on tanks, borewells and lift irrigation. Option D is wrong because Maharashtra is known for modern plastic drip irrigation, not the bamboo system. Exam tip: bamboo drip - Meghalaya, zabo - Nagaland, apatani - Arunachal Pradesh, kuhl - Himachal Pradesh, ahar-pyne - Bihar.

Q311.Indian HistoryAsked in: SSC GD Constable · 13 Jan 2023, Shift 4Medium

The tribal group called 'Santhals' rose in revolt in _______.

  1. A.1876
  2. B.1855
  3. C.1896
  4. D.1860
Show answer

Correct answer: B. 1855

Explanation

The correct answer is B, 1855. The Santhal rebellion, known as the Hul, broke out on 30 June 1855 in the Rajmahal hills of the Santhal Parganas, in what is now Jharkhand. It was led by the brothers Sidhu and Kanhu Murmu, along with Chand and Bhairav, who gathered thousands of Santhals against the moneylenders, traders, zamindars and Company officials who had taken over their land and pushed them into bonded labour. The rising was put down with heavy force by 1856, but it forced the British to carve out a separate Santhal Parganas district with special rules barring outsiders from buying tribal land. Option A is wrong because no Santhal rising took place in 1876. Option C is wrong because 1896 is close to but not the year of the Munda ulgulan of Birsa Munda, which began in 1899. Option D is wrong because by 1860 the rebellion had already been crushed. Exam tip: Santhal Hul 1855 under Sidhu and Kanhu; Munda Ulgulan 1899 to 1900 under Birsa Munda.

Q312.Awards & HonoursAsked in: SSC GD Constable · 14 Feb 2019, Shift 2Medium

Who among the following was nominated for the prestigious Laureus World Sports Awards in 2019?

  1. A.Anirban Chatterji
  2. B.Pankaj Advani
  3. C.Dutee Chand
  4. D.Vinesh Phogat
Show answer

Correct answer: D. Vinesh Phogat

Explanation

The correct answer is D, Vinesh Phogat. The wrestler Vinesh Phogat was nominated in 2019 for the Laureus World Sports Award in the Breakthrough of the Year category, the first Indian athlete to be shortlisted in that category. The nomination followed a remarkable 2018, in which she won gold at the Commonwealth Games at Gold Coast and then gold at the Asian Games in Jakarta, becoming the first Indian woman wrestler to win an Asian Games title. She had already received the Arjuna Award in 2016. The Laureus World Sports Awards, begun in 2000 by the Laureus Sport for Good Foundation, are often called the Oscars of sport. Option A is wrong because Anirban Chatterji is not a Laureus nominee. Option B is wrong because Pankaj Advani, a world champion in billiards and snooker, was not on the list. Option C is wrong because the sprinter Dutee Chand, known for her legal fight over hyperandrogenism rules, was not nominated that year. Exam tip: Vinesh Phogat - Laureus nomination 2019, Asian Games gold 2018, Arjuna Award 2016.

Q313.Indian States & UTsAsked in: SSC GD Constable · 2nd December 2021, Shift 2Medium

In which state of India did the Manikya dynasty rule?

  1. A.Gujarat
  2. B.Rajasthan
  3. C.Manipur
  4. D.Tripura
Show answer

Correct answer: D. Tripura

Explanation

The correct answer is D, Tripura. The Manikya dynasty ruled Tripura for centuries, and its kings all took the title Manikya. Their history is recorded in the Rajmala, a chronicle in Bengali verse first compiled in the fifteenth century under Dharma Manikya. The Ujjayanta Palace at Agartala, built by Radha Kishore Manikya at the beginning of the twentieth century, was their seat and now houses a state museum, and the lake palace Neermahal was raised by Bir Bikram Kishore Manikya, the last ruling king, after whom Agartala's airport is named. The princely state signed the merger agreement and joined the Indian Union in October 1949. Option A is wrong because Gujarat was ruled by the Solanki or Chaulukya line. Option B is wrong because Rajasthan had the Sisodia, Kachwaha and Rathore houses. Option C is wrong because Manipur was ruled by the Ningthouja or Meitei dynasty. Exam tip: Manikya means Tripura, its chronicle is the Rajmala, and it merged with India in 1949.

Q314.Art & CultureAsked in: SSC GD Constable · 22 Nov 2021, Shift 3Medium

The 9th edition of the International Sand Art Festival was organised in December 2020 in ________.

  1. A.Odisha
  2. B.Tamil Nadu
  3. C.Maharashtra
  4. D.Andhra Pradesh
Show answer

Correct answer: A. Odisha

Explanation

The correct answer is A, Odisha. The International Sand Art Festival is held every year on Chandrabhaga beach at Konark in Odisha, and its ninth edition took place in December 2020. The state tourism department organises it alongside the Konark Festival of classical dance, staged at the open-air theatre near the Sun Temple, so that visitors get sculpture on the sand by day and dance in the evening. Artists from India and abroad carve large figures in wet sand along the shore. Odisha has a long association with the art form: Sudarsan Pattnaik of Puri, honoured with the Padma Shri, has won many international sand sculpture titles. Option B is wrong because Tamil Nadu's well known coastal festival is the Mamallapuram dance festival. Option C is wrong because Maharashtra holds the Ellora-Ajanta festival. Option D is wrong because Andhra Pradesh hosts the Visakha Utsav. Exam tip: link Konark in Odisha with three things — the Sun Temple, the Konark dance festival and the International Sand Art Festival at Chandrabhaga beach.

Q315.Indian EconomyAsked in: SSC GD Constable · 18 Feb 2019, Shift 2Easy

The Planning Commission was set up by the Government of India in the year:

  1. A.1948
  2. B.1950
  3. C.1949
  4. D.1951
Show answer

Correct answer: B. 1950

Explanation

The correct answer is B, 1950. The Planning Commission was set up in March 1950 by a resolution of the Union Cabinet, not by the Constitution or by an Act of Parliament, so it was an extra-constitutional and non-statutory body. The Prime Minister was always its chairman, Jawaharlal Nehru being the first, and a full-time Deputy Chairman ran its work. Its task was to assess the country's material, capital and human resources and to draw up Five Year Plans for their balanced use. The First Five Year Plan ran from 1951 to 1956, was based on the Harrod-Domar model and put agriculture and irrigation first. The Commission was replaced on 1 January 2015 by NITI Aayog, a policy think tank that advises but does not allot funds to states. Options A, C and D are wrong because 1948, 1949 and 1951 are each a year off; 1951 is when the First Plan began, not when the body was created. Exam tip: Planning Commission 1950, First Plan 1951-56, NITI Aayog 2015.

Q316.Indian HistoryAsked in: SSC GD Constable · 30 Jan 2023, Shift 4Easy

Why was the year 1757 an important year for the English East India Company in India?

  1. A.In 1757 the English East India Company got control over Hyderabad by defeating the Nizam in the Battle of Plassey.
  2. B.In 1757 the English East India Company got control over Madras by defeating Nawab Siraj-ud-daulah in the Battle of Plassey.
  3. C.In 1757 the English East India Company got control over Oudh by defeating Nawab Siraj-ud-daulah in the Battle of Berar.
  4. D.In 1757 the English East India Company got control over Bengal by defeating Nawab Siraj-ud-daulah in the Battle of Plassey.
Show answer

Correct answer: D. In 1757 the English East India Company got control over Bengal by defeating Nawab Siraj-ud-daulah in the Battle of Plassey.

Explanation

The correct answer is D. The Battle of Plassey was fought on 23 June 1757 on the bank of the Bhagirathi near Palashi in Bengal, and Robert Clive's small Company force defeated Nawab Siraj-ud-daulah there. The victory owed less to fighting than to treachery: the Nawab's commander Mir Jafar kept his troops out of the battle after a secret bargain, and the bankers of Murshidabad backed the plot. Mir Jafar was made Nawab, and the Company won a hold over the trade and revenue of Bengal, which is why 1757 is treated as the start of British political power in India. Option A is wrong because the Nizam of Hyderabad was not a party to Plassey. Option B is wrong because Madras was already a Company settlement and Plassey was fought in Bengal. Option C is wrong because there was no Battle of Berar, and Oudh came under Company influence later. Exam tip: Plassey 1757 against Siraj-ud-daulah, Buxar 1764 against Mir Qasim, Shuja-ud-daula and Shah Alam II.

Q317.Static GKAsked in: SSC GD Constable · 16 Nov 2021, Shift 1Medium

Which of the following set of countries participated in the Malabar Naval Exercise 2020?

  1. A.India, Japan and the US
  2. B.India, Israel and the US
  3. C.India, Australia, Israel and the US
  4. D.India, Australia, Japan and the US
Show answer

Correct answer: D. India, Australia, Japan and the US

Explanation

The correct answer is D, India, Australia, Japan and the US. Malabar 2020 was held in two phases in November 2020, the first in the Bay of Bengal off Visakhapatnam and the second in the Arabian Sea, and Australia joined India, Japan and the United States in it. Malabar began in 1992 as a bilateral naval exercise between the Indian Navy and the US Navy. Japan became a permanent participant in 2015. Australia had taken part once in 2007 and then returned in 2020, which brought the navies of all four Quad countries together in the same exercise. The drills cover anti-submarine warfare, air defence, cross-deck flying and live firing. Option A is wrong because that was the three-nation line-up from 2015 to 2019, before Australia rejoined. Option B is wrong because Israel has never been part of Malabar. Option C is wrong for the same reason, and it also leaves out Japan, a permanent member. Exam tip: Malabar started 1992 as India-US, Japan permanent from 2015, Australia from 2020 — the four Quad navies.

Q318.General ScienceAsked in: SSC GD Constable · 13 Feb 2019, Shift 3Medium

Which juice secreted by the organs in the alimentary canal plays an important role in the digestion of fats?

  1. A.Pancreatic juice, saliva
  2. B.Hydrochloric acid, mucus
  3. C.Bile juice, Pancreatic juice
  4. D.Saliva, hydrochloric acid
Show answer

Correct answer: C. Bile juice, Pancreatic juice

Explanation

The correct answer is C, Bile juice, Pancreatic juice. Fat is digested in the small intestine by these two secretions working together. Bile is made by the liver and stored in the gall bladder; it carries no enzyme, but its bile salts break large fat globules into tiny droplets, a process called emulsification, and they also make the acidic food from the stomach alkaline so that pancreatic enzymes can act. Pancreatic juice is poured into the duodenum and carries lipase, which splits the emulsified fat into fatty acids and glycerol, along with trypsin for protein and pancreatic amylase for starch. Option A is wrong because saliva has only salivary amylase, which acts on starch in the mouth. Option B is wrong because hydrochloric acid only makes the stomach acidic and activates pepsin, while mucus protects the stomach lining. Option D is wrong for both those reasons; neither saliva nor acid digests fat. Exam tip: bile emulsifies and lipase digests; the liver is the largest gland in the human body.

Q319.Environment & EcologyAsked in: SSC GD Constable · 14 Feb 2019, Shift 2Easy

Which of the following is NOT a sustainable development goal targeted to be achieved by 2030?

  1. A.Gender Equality
  2. B.Zero Hunger
  3. C.Good Health and Wellbeing
  4. D.Space Research
Show answer

Correct answer: D. Space Research

Explanation

The correct answer is D, Space Research. Space research is not one of the Sustainable Development Goals. The United Nations General Assembly adopted seventeen such goals in September 2015 as part of the 2030 Agenda for Sustainable Development, with 169 targets to be met by 2030; they replaced the Millennium Development Goals, which ran from 2000 to 2015. The seventeen cover poverty, hunger, health, education, gender equality, clean water, energy, decent work, industry, inequality, cities, responsible consumption, climate action, life below water, life on land, peace and justice, and partnerships. Option A is wrong because Gender Equality is Goal 5. Option B is wrong because Zero Hunger is Goal 2. Option C is wrong because Good Health and Well-being is Goal 3. In India NITI Aayog tracks state progress on the goals through its SDG India Index. Exam tip: 17 goals, 169 targets, adopted 2015, target year 2030; Goal 1 is No Poverty and Goal 17 is Partnerships for the Goals.

Q320.General ScienceAsked in: SSC GD Constable · 9 March 2019, Shift 3Easy

Red algae are generally found in:

  1. A.mountains
  2. B.cities
  3. C.water bodies
  4. D.deserts
Show answer

Correct answer: C. water bodies

Explanation

The correct answer is C, water bodies. Red algae, the division Rhodophyta, live in water, mostly in warm and shallow sea water, with a few species in fresh water. Their colour comes from the pigment phycoerythrin, which masks the green of chlorophyll and lets them use the blue light that reaches greater depths, so some grow deeper than other algae. Porphyra, Gracilaria and Polysiphonia are common examples, and the agar used in laboratories and the carrageenan used in food both come from this group. Coralline red algae deposit calcium carbonate and help build coral reefs. Option A is wrong because bare mountain slopes lack the standing water algae need. Option B is wrong because a city is a settlement, not a water body or habitat for marine algae. Option D is wrong because deserts are dry and an alga cannot complete its life cycle without water. Exam tip: Rhodophyta are red from phycoerythrin, Chlorophyta green from chlorophyll, Phaeophyta brown from fucoxanthin.