Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :

Assertion A : Bottleneck effect is an example of genetic drift.

Reason R : Bottleneck effect leads to random changes in gene frequency due to sudden decrease in population size.

In the light of the above statements. choose the most appropriate answer from the options given below :

A

Both A and R are correct and R is the correct explanation of A

B

Both A and R are correct but R is NOT the correct explanation of A

C

A is correct but R is not correct

D

A is not correct but R is correct