A candidate is required to answer 7 questions out of 12 questions,which are divided into two groups,each containing 6 questions. He is not permitted to attempt more than 5 questions from either group. Find the number of different ways of doing questions.

Question

$\begin{array}{1 1}(A)\;780\\(B)\;782\\(C)\;784\\(D)\;786\end{array}$