With reference to Eutrophication, Which of the following is/are true?

Q. With reference to Eutrophication, Which of the following is/are true?

1. It is phenomenon of nutrient enrichment of a water body

2.  It depletes the water of dissolved oxygen (DO).

3. Human activities are mainly responsible for the eutrophication

Select the correct answer from the following codes

A.            Only 1

B.            Only 1 and 2

C.            Only 2 and 3

D.            1,2 and 3

Answer: 1,2 and 3