Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
\[
\text{Assertion (A): In the context of Philosophy of mind (epiphenomenalism), mental states are the products of brain's neural firing.}
\]
\[
\text{Reason (R): Mental states and brain states are two distinctive states, wherein brain states and mental states are causally connected only in one way.}
\]
In the light of the above statements, choose the most appropriate answer from the options given below: