A stationary hydrogen atom emits photon corresponding to the first line (highest wave length) of Lyman series. If R is the Rydberg constant and M is the mass of the atom, the recoil velocity of the atom is

A

$$\frac{Rh}{4M}$$

B

$$\frac{3Rh}{M}$$

C

$$\frac{3Rh}{4M}$$

D

$$\frac{Rh}{M}$$