Assertion: Time taken for the completion of `75%` of a Ist order reaction is double than its `t_(.^(1)//_(2))`.
Reason: Time taken for completion of any fraction of a Ist order reaction is a constant value.
A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
C. If assertion is true but reason is false.
D. If assertion is false but reason is true.