Two identical γ-ray photons each strike free electrons that are initially at rest. For photon A the scattering angle of the photon is 15∘, while for photon B it is 135∘. Which of the following statements best describes the kinetic energies KA and KB of the recoil electrons?
a) KA=KB because the incident photons have the same energy.
b) KA>KB because a smaller scattering angle corresponds to greater momentum transfer to the electron.
c) KA<KB because a larger scattering angle corresponds to a larger wavelength increase of the photon.
d) KA\, and KB cannot be compared without knowing the initial photon wavelength.