$\begin{align*} \int_0^{\pi/2} \sin^6 x \cos^5 x \; dx \end{align*}$ is equal to :

Question

( A ) $\frac{4}{693}$
( B ) $\frac{5}{693}$
( C ) $\frac{10}{693}$
( D ) $\frac{8}{693}$