Martyrs' Day or Shaheed Diwas, observed on 30 January, marks the death anniversary of whom?

The correct answer is C, Swami Vivekananda, who was born on 12 January 1863. The Government of India chose his birth anniversary for National Youth Day because his writings and speeches were addressed above all to the young, and his address at the Parliament of Religions in Chicago in 1893 remains the best known moment of his life.

Option A, Subhas Chandra Bose, was born on 23 January 1897, and that date is observed as Parakram Diwas, so the two January anniversaries are often placed against each other. Option B, Lala Lajpat Rai, was born on 28 January 1865 and is remembered as Punjab Kesari. Option D, Bhagat Singh, is associated with 23 March, the day he was executed in 1931, which is also observed as a Martyrs' Day. Keep the January anniversaries in order: 12th for Vivekananda, 23rd for Bose and 28th for Lajpat Rai.

The correct answer is B, 15 January. On that date in 1949, Field Marshal K. M. Cariappa took over as the first Indian Commander-in-Chief of the Indian Army from the last British officer to hold the post, and the day marks the passing of command into Indian hands.

Option A, 4 December, is Indian Navy Day. Option C, 8 October, is Indian Air Force Day, marking the raising of the force in 1932. Option D, 26 January, is Republic Day, on which the armed forces take part in the parade, which is why students sometimes attach the army to that date. The Coast Guard completes the set with 1 February. Examiners frequently place all the service days in one question, so learn them together: Army 15 January, Coast Guard 1 February, Air Force 8 October and Navy 4 December.

The correct answer is D, the Ramsar Convention, the Convention on Wetlands signed in the Iranian town of Ramsar on 2 February 1971. Wetlands listed for protection under the treaty are called Ramsar sites, and the name of the town has become the name of the agreement.

Option A, the Basel Convention, deals with the movement of hazardous wastes across national borders. Option B, CITES, is the Convention on International Trade in Endangered Species of Wild Fauna and Flora, which regulates trade in threatened plants and animals. Option C, the Montreal Protocol, controls substances that deplete the ozone layer and is paired in papers with 16 September, the International Day for the Preservation of the Ozone Layer. All four are genuine environmental treaties, so the safest method is to attach each one to its own subject and date.

The correct answer is B, the announcement of the Raman Effect. C. V. Raman announced his discovery of the scattering of light that carries his name on 28 February 1928, and he was awarded the Nobel Prize in Physics for it in 1930. The Government of India designated the date as National Science Day in 1986 and the first observance was held in 1987.

Option A, the discovery of the neutron by James Chadwick, also belongs to the early 1930s but has no connection with any Indian observance. Option C, the discovery of penicillin by Alexander Fleming, is a landmark in medicine and is placed here only as a plausible science event. Option D, the launch of Aryabhata, India's first satellite, took place in 1975 and is associated with the Indian space programme rather than with Science Day. Hold the three elements together: Raman, 1928 and 28 February.

The correct answer is C, 21 February. The day was declared by UNESCO to promote linguistic and cultural diversity and to protect languages that are dying out, and the date recalls the language movement in Dhaka in 1952, in which students were killed while demanding recognition for Bengali.

Option A, 10 January, is World Hindi Day, which marks the first World Hindi Conference held in 1975, and it is the commonest wrong answer because both days are about language. Option B, 13 February, is World Radio Day, and in India the same date is National Women's Day for the birth anniversary of Sarojini Naidu. Option D, 26 January, is Republic Day. A related date worth carrying is 14 September, observed in India as Hindi Diwas, which is different again from World Hindi Day.