$\bigg( \large\frac{4}{3} $$m -\frac{3}{4}n\bigg)^2 +2nm=?$

Question

$\begin{array}{1 1} \large\frac{16}{9} m^2+\frac{9}{16}n \\ \frac{16}{9}m^2+\frac{9}{16}n^2 \\ none\;of\;these \\ \frac{16}{9}m+\frac{9}{16}n^2 \end{array} $