In which group of states does the Luni River flow?

Correct — B. The Luni rises in the Aravalli range near Ajmer in Rajasthan, runs south-west across the Marwar tract, and ends in the Rann of Kutch in Gujarat — so option (b) names the two states it flows through.

It is an inland river. It never reaches the sea, draining instead into the marshes of the Rann, and its water turns brackish downstream, which is where the name comes from: lavana, salt.

Why the others are wrong

• (a)
  Maharashtra and Karnataka — Maharashtra and Karnataka are drained by the Godavari, Bhima and Krishna headwaters rising in the Western Ghats, not by an Aravalli river.
• (c)
  Bihar and West Bengal — Bihar and West Bengal lie in the Ganga basin, a Himalayan-fed system entirely separate from the Luni's course.
• (d)
  Andhra Pradesh and Telangana — Andhra Pradesh and Telangana sit in the Krishna and Godavari basins of the eastern peninsula, far from a river that ends in the Rann of Kutch.

Most Indian rivers end in the Bay of Bengal or the Arabian Sea. A third category, inland drainage, ends in a lake, a marsh or the sand — and western Rajasthan is where India's inland drainage sits.

The Aravalli range is the watershed. Streams on its western flank are seasonal and shallow, and the Luni is the largest of them.

Its lower course crosses into Gujarat and disperses in the Rann of Kutch, so the river belongs to two states even though it is thought of as a Rajasthan river.

Key facts

• The Luni rises in the Aravalli range in Rajasthan and drains into the Rann of Kutch in Gujarat.
• The Luni is the largest river of Rajasthan's inland drainage and does not reach the sea.
• Its water is saline downstream, and the name comes from lavana, the word for salt.
• The Sabarmati and the Mahi are the neighbouring west-flowing rivers that do reach the Arabian Sea.

Common traps

• Assuming every west-flowing river reaches the Arabian Sea, when the Luni ends in the Rann.
• Stopping at Rajasthan and missing the Gujarat half of the course.

No directly related past PYQ was found.