Which one of the following pairs of cities have the largest annual average rain difference as compared to the other three pairs?

Mumbai and Pune have the largest annual average rain difference as compared to the other three pairs. Mumbai/ Bombay receives on balance 2168 mm (85.4 in) of rainfall per year, or 180.7 mm (7.1 in) per month. In Pune, the monsoon lasts from June to October, with moderate rainfall and temperatures ranging from 22 to 28° C (72 to 82° F).