Soil erosion is a serious environmental problem. Steps should be taken to curb this problem. Following are some ways to prevent soil erosion:

1. Plant trees on barren lands to prevent soil erosion.

2. Add mulch and rocks to trap plants and grass beneath to prevent soil erosion.

3. Mulch matting can be used to reduce erosion on slopes.

4. Place a series of fiber logs to prevent any water or soil from flowing away.

5. A wall at the base of a slope can help prevent soil erosion.

6. Every house should have proper drainage system so that water can flow into proper water collection systems.

7. Afforestation is the planting of trees on a large scale to check soil erosion. 

The sperm cell is the smallest cell in the human body. The volume of these cells is quite tiny. The head of a sperm cell is roughly 4 micrometres long, about the same size as a red blood cell (RBCs). Egg cells are the biggest cells in the human body (ovum).

The father of the Indian Space Programme is often considered to be:

(C) Vikram Sarabhai

Dr. Vikram Sarabhai, an eminent scientist, visionary, and the founder of the Indian Space Research Organisation (ISRO), is widely regarded as the father of the Indian Space Programme. He played a pivotal role in establishing and nurturing India's space capabilities. Dr. Sarabhai was instrumental in the launch of India's first satellite, Aryabhata, in 1975, marking a significant milestone in the country's space exploration journey. His vision and leadership laid the foundation for the development of ISRO and the growth of India's space capabilities, making space exploration an integral part of the country's scientific and technological advancements.