How can the extent of water pollution by organic wastes by determined?

How can we control water pollution ?

Two questions consist of two statements each, printed as Assertion and Reason. While answering these questions, you are required to choose any one of the followng four responses. If both Assertion and Reason are true and Reason is a correct explanation of Assertions. If both Assertion and Reason are true but Reason is not a correct explanation of Assertion. If Assertion is true but Reason is false. If both Assertion and Reason are false. Assertion:BOD indicates the extent of water pollution by organic wastes. Reason:Increase in BOD decreases dissolved oxygen of waste water.

What is water pollution ?

What is water pollution ?

What are the effects of water pollution ?

What are the causes of water pollution ?

What are the sources of water pollution ?

How can we control the pollution of river ganga?