If Two Photons in a Vacuum Have Different Energies, What

Multiple Choice

If two photons in a vacuum have different energies, what can be said about the wavelengths of the photons?

A) The higher-energy photon has the shorter wavelength.
B) The higher-energy photon has the longer wavelength.
C) The two photons have the same wavelength; all photons have the same wavelength, regardless of energy.
D) We cannot say anything; wavelength depends only on color, not on energy.