Consider an initially pure `M gm` sample of `X`, an isotope that has a half-life of `T` hour, what is its initial decay rate (`N_A` = Avogadro No, atomic weight of `X` is `A`)

A. `(M N_(A))/(T)`

B. `(0.693 M N_(A))/(T)`

C. `(0.693 M N_(A))/(AT)`

D. `(2.303 M N_(A))/(A T)`