Assertion:In a reversible exothermic,$E_{act}$ of forward $Rx^n$ is lower than that of backward $Rx^n$.Reason :The threshold energy of forward reaction is less than that of backward $Rx^n$

Question

$\begin{array}{1 1}(a)\;\text{Assertion is correct reason is correct explanation of assertion}\\(b)\;\text{Assertion is correct reason is not correct explanation of assertion}\\(c)\;\text{Assertion is not correct reason is correct}\\(d)\;\text{Assertion is correct reason is incorrect}\end{array}$