Assertion (A): The surface winds spiral inwards upon the centre of the cyclone. Reason (R): Air descends in the centre of the cyclone.

Answer: (c) A is true but R is false

Winds converge towards the low at the surface (A true), and the air rises there (R false).

The idea

A cyclone has a low-pressure centre that draws surface air inward. The converging air generally rises, allowing clouds and rain to develop. An anticyclone generally combines surface outflow with descending air. The small eye of an intense tropical cyclone is an exception within the larger rising circulation.

Low pressure draws surface air inward → Rotation curves the inflow → Converging air rises in the storm → Rising air expands and cools → Condensation builds cloud and rain

Why the others are wrong

(a) R is false.

(b) R is false.

(d) A is true — surface convergence defines a cyclone.

The trap

Air sinks in an ANTIcyclone. Only the small eye of a tropical cyclone has sinking air.

Elimination technique

Separate the general cyclone circulation from the special eye. Surface convergence makes A true, while general descent describes an anticyclone, making R false in this context. The assertion-reason code is therefore (c).

Also know

The eyewall around a tropical cyclone’s eye contains the strongest winds and intense ascent. Extratropical cyclones usually develop along fronts and do not have the same clear tropical eye. Northern cyclones rotate anticlockwise; southern cyclones rotate clockwise. Tropical storm strength and eye development are related, but not every cyclone has an eye.