If $\sin \theta=-\large\frac{4}{5}$ and $\theta$ lies in third quadrant then the value of $\cos\large\frac{\theta}{2}$ is

Question

$\begin{array}{1 1}(A)\;\large\frac{1}{5}&(B)\;\large\frac{-1}{\sqrt {10}}\\(C)\;\large\frac{-1}{\sqrt 5}&(D)\;\large\frac{1}{\sqrt{10}}\end{array} $