- a.(II) only
- b.(I), (II) and (III)
- c.(II) and (III)
- d.(III) only
Answer: (A) (II) only
Statement I is acceptable: a cyclone is a system of winds converging on a low-pressure centre, so it is driven by a difference in air pressure. Statement II is correct: tropical cyclones form over seas warmer than about $27^\circ$C, mostly between $5^\circ$ and $20^\circ$ latitude. Statement III is wrong: the eye is a calm, largely cloud-free area of sinking air with the lowest pressure and a relatively high temperature, while the densest clouds, strongest winds and heaviest rain are in the surrounding eyewall. The correct combination, (I) and (II), is not among the options, so PSC's final key marks this question '*' and gives 1 mark to all candidates. Extras: cyclones rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern, do not form within about $5^\circ$ of the Equator, and are called hurricanes in the Atlantic and typhoons in the north-west Pacific; the Bay of Bengal produces more cyclones than the Arabian Sea.