Q. With reference to sources of water pollution, which of the following is/are true?
1. Natural sources
2. Domestic sources
3. Agricultural sources
4. Industrial sources
Select the correct answer from the following codes
a. Only 4
b. Only 2, 3 and 4
c. Only 3 and 4
d. 1,2, 3 and 4
Answer: 1,2, 3 and 4
