The Formula for the De Broglie Wavelength of a Particle $E = p \mathrm { c }$

The formula for the de Broglie wavelength of a particle follows readily from the relations between energy E and frequency for light, frequency and wavelength for waves, and the specific relation between energy E and momentum p given in the equation

A) $E = p \mathrm { c }$ , for a photon.
B) $E = \frac { p ^ { 2 } } { 2 m }$ , for a Newtonian particle in motion.
C) $E ^ { 2 } = ( p c ) ^ { 2 } + \left( m c ^ { 2 } \right) ^ { 2 }$ , for a relativistic particle in motion.
D) $E = m \mathrm { c } ^ { 2 }$ , for a relativistic particle at rest.