When the Electron in a Hydrogen Atom Falls from Its $\lambda$

Multiple Choice

When the electron in a hydrogen atom falls from its first excited energy level to the ground state energy level, a photon with wavelength $\lambda$ is emitted. A proton having this same wavelength would have a velocity of

A) 3.87 m/s
B) 5990 m/s
C) 1.21 * 10^-7 m/s
D) 3.26 m/s
E) 5.99 m/s