The correct answer is "2 only" because soil erosion in India is significantly exacerbated by deforestation, which leads to the loss of vegetation that stabilizes the soil. As trees and plants are removed, the soil loses its protective cover, making it more susceptible to erosion from water and wind. In contrast, terrace cultivation is a practice designed to combat erosion by creating step-like fields that reduce runoff, while tropical climate itself does not directly contribute to soil erosion but influences the types of vegetation and soil management practices.