question_answer

Assertion: The reaction.\[A+B\](excess)\[\xrightarrow[{}]{k}C,\]for which\[\xrightarrow[dt]{d[C]}\propto [A],\]follows the first order kinetics. Reason: The order of a reaction is the number of molecules whose concentration determines the rate of reaction at a given temperature.

A)  both assertion and reason are true: and reason is the correct explanation of assertion

B)  both assertion and reason are true: but reason is NOT the correct explanation of assertion

C)  assertion is true but reason is false

D)  assertion is false but reason is true