Which One of the Following Statements Describes the Stiles-Crawford Effect

Multiple Choice

Which one of the following statements describes the Stiles-Crawford effect?

A) Photons arriving near the edge of the pupil are less likely to be absorbed.
B) Photons are some frequencies are less likely to be absorbed by a photoreceptor than those at other frequencies
C) Only two-thirds of the photons absorbed by a photoreceptor actually result in a response
D) When a photon is absorbed, its effect on a photoreceptor is the same regardless of the photon's wavelength.