Assertion: For a first order reaction, the concentration of the reactant decreases exponentially with time.
Reason: Rate of reaction at any time depend upon the concentration of reactant at that time.
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.