Correct Option
Option (d):
Assertion (A) states that Bangalore receives much higher average annual rainfall than Mangalore. This statement is false. Bangalore, situated in the interior Deccan Plateau, receives an average annual rainfall of approximately 900 mm. In contrast, Mangalore, located on the windward side of the Western Ghats along the Karnataka coast, receives a significantly higher average annual rainfall, often exceeding 3,500 mm, primarily from the southwest monsoon. Therefore, Assertion (A) is factually incorrect.
Reason (R) states that Bangalore has the benefit of receiving rainfall both from southwest and northeast monsoons. This statement is true. Bangalore indeed receives rainfall from two distinct monsoon systems:
- The Southwest Monsoon (June to September), which is the primary source of rainfall for much of India.
- The Retreating Northeast Monsoon (October to November), which brings rainfall to parts of South India, including Bangalore.
Despite this dual influence, the total volume of rainfall received by Bangalore is considerably less than that received by Mangalore due to its geographical location and the strong orographic effect on the Western Ghats.
Since Assertion (A) is false and Reason (R) is true, option (d) is the correct choice.
Incorrect Options
Options (1), (2), and (3) are incorrect because they either assume Assertion (A) to be true, or Reason (R) to be false, or both to be true. As established, Assertion (A) is false because Mangalore receives substantially more rainfall than Bangalore, and Reason (R) is true as Bangalore benefits from both southwest and northeast monsoon rainfall. Therefore, any option that contradicts these facts is incorrect.