What is the main reason of higher humidity in the Eastern Bihar?

The correct answer is: A. Nearness to sea

The Eastern Bihar is located in the Ganges Delta, which is a low-lying region that is bordered by the Bay of Bengal to the south. The Bay of Bengal is a large body of water that has a high evaporation rate, which means that it releases a lot of water vapor into the atmosphere. This water vapor then travels inland and contributes to the high humidity levels in Eastern Bihar.

The other options are incorrect because:

• Option B: Cyclonic effect. Cyclonic effects are caused by the interaction of warm and cold air masses. They are not a major factor in the high humidity levels in Eastern Bihar.
• Option C: Nearness to Himalayas. The Himalayas are a mountain range that is located to the north of Eastern Bihar. They block the flow of cold air from the north, which helps to keep the temperatures in Eastern Bihar relatively high. However, they do not have a significant impact on the humidity levels in the region.
• Option D: None of the above. This option is incorrect because the main reason for the high humidity levels in Eastern Bihar is the nearness to sea.