Let $S = \{ 1,2,3 , \ldots , 100 \}$, then number of non-empty subsets $A$ of $S$ such that the product of elements in $A$ is even is :\\
(1) $2 ^ { 100 } - 1$\\
(2) $2 ^ { 50 } + 1$\\
(3) $2 ^ { 50 } \left( 2 ^ { 50 } - 1 \right)$\\
(4) $2 ^ { 50 } - 1$