Let $\alpha, \beta$ be such that $\pi - \alpha - \beta < 3 \pi$. If $\sin \alpha + \sin \beta = -\frac{21}{65}$ and $\cos \alpha + \cos \beta = -\frac{27}{65}$, then the value of $\cos \frac{\alpha - \beta}{2}$ is

Question

( A ) $\frac{3}{\sqrt{130}}$
( B ) $\frac{6}{65}$
( C ) $-\frac{3}{\sqrt{130}}$
( D ) $-\frac{6}{65}$