$A$ billiard table has length and width as shown in the figure. $A$ ball is placed at point $A$. At what angle $\theta$ should the ball be projected so that after colliding with two walls,the ball will fall into the pocket $B$? Assume that all collisions are perfectly elastic and neglect friction.

• A
  $\theta = \cot^{-1} \frac{2a - c}{2b}$
• B
  $\theta = \cot^{-1} \frac{2a - c}{b}$
• C
  $\theta = \tan^{-1} \frac{c - a}{2b}$
• D
  $\theta = \cot^{-1} \frac{c - a}{b}$