Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A):	There is always a sharp decline in dissolved oxygen downstream from the point of sewage discharge, which causes mortality of fish and other aquatic creatures
Reason (R):	Micro-organisms involved in bio-degradation of organic matter in the receiving water body consume a lot of oxygen

In the light of the above statements, choose the correct answer from the options given below:

1.	Both (A) and (R) are True and (R) is the correct explanation of (A).
2.	Both (A) and (R) are True but (R) is not the correct explanation of (A).
3.	(A) is True but (R) is False.
4.	(A) is False but (R) is True.