The Alpine vegetation in the western Himalayas is found only up to a height of 3000 metres, while in the eastern Himalayas it is found up to a height of 4000 metres, The reason for this variation in the same mountain range is that

The correct option is C because of the combined effect of latitude and moisture. The Eastern Himalayas are located at a lower latitude closer to the equator and receive significantly higher rainfall from the Bay of Bengal branch of the monsoon. This higher humidity and warmer temperature create a more favorable environment for plant growth, allowing the tree line and alpine vegetation to extend to higher altitudes. In contrast, the Western Himalayas are farther from the equator and receive less rainfall, making the environment drier and colder at lower elevations, which restricts alpine vegetation to a maximum height of around 3000 metres.