Monsoon rainfall in India is influenced by multiple factors, not just one. While distance from the sea does have some influence, it's not the only factor.
Topography is crucial because mountains and highlands create orographic effects - when moisture-laden winds are forced to rise over these elevations, they cool and condense, resulting in heavy rainfall on windward slopes (like the Western Ghats receiving heavy rainfall during southwest monsoon). Areas in rain shadow regions receive much less rainfall.
Cyclonic depressions, especially those forming in the Bay of Bengal, significantly contribute to monsoon rainfall patterns. These low-pressure systems help pull the monsoon winds inland and cause heavy precipitation as they move across the subcontinent. The frequency and path of these depressions create variations in rainfall distribution across different regions.
The first option stating "Only the distance from the sea influences monsoon rainfall" is incorrect because it suggests a single factor determines monsoon rainfall, which is an oversimplification of the complex monsoon system.