A light string of mass m and length L has its ends tied to two walls that are separated by the distance D. Two objects each of mass M are suspended from the string as shown in figure. if a wave pulse is sent from point A how long does it take to reach point B?

Question

$(A) \large\sqrt \frac{MgL \tan\theta}{4m} \quad$ $(B) \large\sqrt \frac{Mg L}{m \tan \theta} \quad$$(C) \large\sqrt \frac{M L\tan\theta}{4mg} \quad$$ (D) \large\sqrt \frac{mL \tan\theta}{4Mg}$