The northern plain of the Indian subcontinent has been formed by the interplay of the three major river systems along with their tributaries. Choose the odd one out of the options given.

Correct — D. The northern plain was built from the alluvium of the Indus, the Ganga and the Brahmaputra and their tributaries. The Godavari is not one of the three.

The Godavari is a peninsular river: it rises at Trimbakeshwar in the Western Ghats of Maharashtra and drains east into the Bay of Bengal, laying its sediment in its own delta on the east coast. That places option (d) outside the group.

Why the others are wrong

• (a)
  The Indus — The Indus rises in Tibet and its tributaries built the western section of the plain, the Punjab plain. It is one of the three named systems.
• (b)
  The Brahmaputra — The Brahmaputra enters India in Arunachal Pradesh and lays down the Assam plain, the easternmost section. It is one of the three named systems.
• (c)
  The Ganga — The Ganga and its tributaries formed the long middle stretch of the plain. It is named in the very sentence the question paraphrases.

The Northern Plain is an alluvial trough between the Himalayas and the peninsular plateau, filled over millions of years by silt from three Himalayan river systems — the Indus, the Ganga and the Brahmaputra.

Himalayan rivers are perennial, fed by snowmelt as well as rain, and they carry heavy silt loads. Peninsular rivers are rain-fed and seasonal, run in shallow valleys already cut into hard rock, and carry far less alluvium.

The Godavari is the longest of the peninsular rivers and is often called the Dakshina Ganga, the Ganga of the south — a nickname that makes it easy to misfile.

Key facts

• The northern plain was formed by the Indus, the Ganga and the Brahmaputra systems along with their tributaries.
• The Godavari is a peninsular river rising at Trimbakeshwar in Nashik district, Maharashtra, and flowing east to the Bay of Bengal.
• The Godavari is the longest river of peninsular India.
• Himalayan rivers are perennial and silt-laden, while peninsular rivers are seasonal and rain-fed.

Common traps

• Treating the Godavari as northern because of the name Dakshina Ganga. The nickname is about size, not location.
• Assuming any long Indian river must be Himalayan. The Godavari is long and entirely peninsular.

No directly related past PYQ was found.