Brahmaputra is an example of ______ drainage.

Answer: (b) Antecedent

The Brahmaputra is antecedent — it kept cutting down as the Himalaya rose.

The idea

An antecedent river establishes its course before the land across that course rises. If downcutting keeps pace with uplift, the river keeps crossing the new mountain barrier. The test is the timing of river establishment relative to mountain growth.

River establishes a course → Land across the course begins to rise → River cuts down into the rising rock → Downcutting keeps pace with uplift → An across-range gorge preserves the older route

Why the others are wrong

(a) Annular drainage forms around domes.

(c) Superimposed drainage is inherited from an overlying layer.

(d) Radial drainage flows out from a dome or volcano.

The trap

Antecedent vs superimposed — both cut across structures.

Also know

Indus and Sutlej are other standard antecedent examples. The Brahmaputra is called Yarlung Tsangpo in Tibet and turns around Namcha Barwa before entering Arunachal Pradesh. Superimposed drainage inherits a pattern from a cover of younger rock later removed by erosion; it need not predate uplift. Radial drainage spreads away from a dome or peak.