For the De Broglie Wavelengths of an Electron and of a Proton

Multiple Choice

For the de Broglie wavelengths of an electron and of a proton to be equal, the electron must travel

A) much faster than the proton.
B) much slower than the proton.
C) at the same speed as the proton.
D) Hold it! Speed is irrelevant; mass is what counts.