Find the missing fraction $\frac{5}{6} + \frac{8}{12} = \frac{7}{4} -$____

Question

$\begin{array}{11} (a)\; \frac{4}{12} \\ (b)\; \frac{3}{12} \\ (c)\; \frac{3}{2} \\ (d)\; \frac{2}{3} \end{array}$