Both the grammars will produce a finite language .Since a language is infinite if we have recursion on start symbol of a language i.e. recursion should be applied on start symbol directly or indirectly.But no such recursion on S which is the start symbol for both of the above grammars.
Hence C) should be the correct option.
I would like to add one fact here that not every recursion leads to infinite language.
e.g. S --> ab
A --> aA
So if we consider S as the start symbol in the above grammar then A has no role in forming strings of the language ,or in other words A has no role in sentential form of a string.Hence the given language only produces {a} and hence is finite and as we can see the recursion due to A is useless.
