The angle between two vectors $\overrightarrow{a}$ and $\overrightarrow{b}$ with magnitudes $\sqrt 3$ and 4,respectively,and $\overrightarrow{a}.\overrightarrow{b}=2\sqrt 3$ is

Question

$$(A)\;\frac{\pi}{6}\quad(B)\;\frac{\pi}{3}\quad(C)\;\frac{\pi}{2}\quad(D)\;\frac{\pi}{4}$$