Punjab and Haryana receive rainfall from

Answer: (a) Westerly disturbances

Western disturbances bring winter rain to Punjab and Haryana. They explain the winter contribution, rather than all rainfall through the year.

The idea

A place can receive rain from different weather systems in different seasons. North-west India receives much of its rain during the summer monsoon and smaller but useful amounts from winter western disturbances. Winter rainfall therefore cannot be treated as the only source of rainfall throughout the year.

Winter westerly circulation → Western disturbance approaches → Moist air reaches the north-west → Uplift forms clouds → Plains receive rain → High mountains receive snow

Why the others are wrong

(b) The Bay of Bengal branch of the monsoon does reach Punjab in summer.

(c) Both systems can contribute: western disturbances in winter, and inland-moving Bay of Bengal systems during the summer monsoon.

The trap

A winter-rain source is not automatically the source of all annual rain. Always check whether the question limits the season.

Also know

Bay of Bengal low-pressure systems can move inland and help summer rain reach the north-west. Punjab and Haryana grow winter wheat, for which gentle winter rain can be useful. Excess rain near harvest can instead damage the crop.