Two spheres A and B of masses m1 and m2 respectively collide. A is at rest initially and B is moving with velocity v along x-axis. After collision B has a velocity$\frac{v}{2}$ in a direction perpendicular to the original direction. The mass A moves after collision in the direction.

Question

( A ) $\theta = tan^{–1} (-\frac{1}{2}) $ to the x-axis
( B ) $\theta = tan^{–1} (\frac{1}{2}) $ to the x-axis
( C ) opposite to the of B
( D ) same as that of B