Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion(A): All vertebrates are chordates but all chordates are not vertebrates
Reason (R):Notochord is replaced by vertebral column in the adult vertebrates
In the light of the above statements,choose the correct answer from the options given below:

Options

A. Both (A) and (R) are coorect and (R) is the correct explanation of (A)
B. Both (A) and (R) are coorect 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