# Let $\cos (\alpha + \beta) = \frac{4}{5}$ and let $\sin (\alpha - \beta) = \frac{5}{13}$, where $0 \leq \alpha, \; \beta \leq \frac{\pi}{4}$, then $\tan 2 \alpha =$
( A ) $\frac{56}{33}$
( B ) $\frac{25}{16}$
( C ) $\frac{20}{7}$
( D ) $\frac{19}{12}$