$\begin{array}{1 1}(A) \;6\sqrt 7+\large\frac{3}{2}\normalsize \sqrt 6\\(B)\;6\sqrt 7- \large\frac{3}{2}\normalsize \sqrt 6\\(C)\;\large\frac{3}{2}\normalsize \sqrt 6-6\sqrt 7 \\(D)\;-6\sqrt 7-\large\frac{3}{2}\normalsize \sqrt 6\end{array}$