Jaipur, the capital of Rajasthan, was founded in 1727 by:

The correct answer is B, Rajasthan. Rajasthan covers about 342,239 square kilometres, roughly a tenth of the area of India, and has been the largest state since Madhya Pradesh was divided in 2000. It is bounded by Punjab, Haryana, Uttar Pradesh, Madhya Pradesh and Gujarat, and it has the longest stretch of India's international border with Pakistan.

Option A, Madhya Pradesh, is the second largest state and was the largest before Chhattisgarh was carved out of it. Option C, Maharashtra, is third by area but first among these in population. Option D, Uttar Pradesh, is the most populous state of India but stands fourth in area. Candidates who remember the population order rather than the area order pick Uttar Pradesh, which is the trap the question is built on.

The correct answer is A, Sirohi. Guru Shikhar, about 1,722 metres high, stands on Mount Abu in Sirohi district and is the highest point both of the Aravallis and of Rajasthan. Mount Abu is the only hill station in the state and also holds the Dilwara Jain temples, famous for their marble carving, and the Nakki Lake.

Option B, Udaipur, has the Aravalli hills around it and the Zawar zinc mines, but not the highest peak. Option C, Ajmer, has Taragarh hill and the source region of the Luni, and is well below Guru Shikhar. Option D, Rajsamand, contains Kumbhalgarh and the Khamnor hills where the Banas rises, and lies close to Haldighati. Remember the chain: Guru Shikhar on Mount Abu in Sirohi district. Sirohi also borders Gujarat, and the Aravallis reach their broadest spread in this southern part of the state.

The correct answer is C, Chambal. The Chambal enters Rajasthan from Madhya Pradesh and flows north and then east through deep ravines, carrying water through the year, which makes it the only perennial river of the state and also its longest. The Rana Pratap Sagar and Jawahar Sagar dams stand on it, and the Chambal ravines are a protected area for the gharial.

Option A, the Luni, dries in stretches and is saline in its lower course. Option B, the Banas, flows entirely within Rajasthan but is seasonal, filling after the monsoon and thinning in summer. Option D, the Ghaggar, is a lost river whose dry bed passes Kalibangan and disappears in the sands of Hanumangarh and Sriganganagar. Rajasthan's dependence on the Chambal and on canal water follows directly from this.

The correct answer is B, the Rann of Kutch. The Luni rises in the Aravallis near Ajmer, flows south west across the desert districts of Marwar, grows saline as it picks up salts from the soil, and ends in the marshes of the Rann of Kutch in Gujarat without reaching open sea. Its name comes from lavanavari, meaning salt water, and it is the main river of western Rajasthan.

Option A is wrong because the Luni is a river of inland drainage and has no mouth on the Arabian Sea. Option C is wrong because the Luni never meets the Chambal, which flows on the other side of the Aravallis; the Banas is the river that joins the Chambal. Option D is wrong because no Rajasthan river drains east to the Bay of Bengal. Sabarmati, Mahi and Luni are the western rivers, and only the Mahi and the Sabarmati reach the Gulf of Khambhat.

The correct answer is A, Rajasthan. Sambhar Lake lies west of Jaipur, spread over parts of Jaipur, Nagaur and Ajmer districts. It is the largest inland saline lake in the country, a major source of common salt, a Ramsar site, and a winter feeding ground for flamingos and other migratory birds.

Option B, Gujarat, has Nal Sarovar and the salt flats of the Rann, but these are not the same as Sambhar. Option C, Odisha, has Chilika, which is the largest brackish water lagoon in India, joined to the sea, and therefore not an inland saline lake. Option D, Andhra Pradesh, has Kolleru and Pulicat, both of them freshwater or brackish coastal lakes. The pair to fix is Sambhar as the largest inland saline lake and Chilika as the largest brackish lagoon.