The correct answer is: a) High rainfall.
Arunachal Pradesh is a state in northeastern India. It is the largest state in India by area, and it is also the most sparsely populated state. The climate of Arunachal Pradesh is tropical monsoon, with a long, hot, and humid summer and a short, cool, and dry winter. The average annual rainfall in Arunachal Pradesh is about 2,500 mm (100 in).
The high rainfall in Arunachal Pradesh is caused by the state’s location in the eastern Himalayas. The Himalayas are a mountain range that runs along the northern border of India. The Himalayas block the moisture-laden winds from the Indian Ocean, causing the winds to rise and cool. As the winds rise, they lose their moisture, which falls as rain on the eastern side of the Himalayas.
The high rainfall in Arunachal Pradesh has a major impact on the soil formation in the state. The rain helps to break down the rocks and minerals in the soil, and it also helps to transport the eroded material to other areas. The high rainfall also helps to keep the soil moist, which is necessary for plant growth.
The other options are incorrect because they do not have a major impact on the soil formation in Arunachal Pradesh. Extreme temperatures can cause the soil to dry out, but they do not have a major impact on the soil formation. Low humidity can also cause the soil to dry out, but it does not have a major impact on the soil formation. Strong winds can cause the soil to erode, but they do not have a major impact on the soil formation.