Explanation:

- L. Dumont (Option 1): He is a French sociologist and anthropologist known for his study of the Indian caste system. He introduced the idea of "purity and pollution" as a key concept in understanding caste hierarchy. However, the specific phrase "respect of pollution" is not directly attributed to him.

- Milton Singer (Option 2): An American anthropologist who worked extensively on Indian civilization and urban cultures, but did not coin the concept "respect of pollution".

- S.C. Dube (Option 3): An Indian sociologist known for studies on Indian villages and modernization, not directly connected to the "respect of pollution" idea.

- E.B. Harper (Option 4): He wrote about the "respect for pollution" in Indian society, particularly regarding untouchability and ritual pollution.

Correct Answer: Option 4: E.B. Harper