Assertion:
The environmentalists are strongly opposed to the use of polythene bags.
RI. Polythene harms land as it never gets decomposed.
RII. Polythene bags are not made of natural products.
Answer: A
RI : This explains the cause for the opposition of the environmentalists towards polythene bags and is valid.
RII : If polythene is made using natural products which do not harm the environment, then it would not be a problem for the environmentalists. However, it could be a problem only when the natural products used in the bags are themselves dangerous to earth in one way or the other but this is not explained by RII. Hence, it is not a valid reason.