An electron of mass `m` when accelerated through a potential difference `V` has de - Broglie wavelength `lambda`. The de - Broglie wavelength associated with a proton of mass `M` accelerated through the same potential difference will be
A. `(lambda m)/(M)`
B. `lambda sqrt((m)/(M))`
C. `(lambda M)/(m)`
D. `lambda sqrt((M)/(m))`