The Correct Option is C
Solution and Explanation
According to the given circuit,
$Y_{1} =\overline{A\cdot B}$
$Y = \overline{(\overline{A\cdot B})\cdot (\overline{A\cdot B})}$
From De Morgan's law,
$Y = \overline{\overline{AB}}{+}\overline{\overline{AB}}{=}\overline{\overline{AB}}$
Y = AB