The Redshift of the Galaxies Is Correctly Interpreted As

Multiple Choice

The redshift of the galaxies is correctly interpreted as:

A) a Doppler shift due to the random motions of galaxies in space.
B) an aging of light as gravity weakens with time.
C) space itself is expanding with time, so the photons are stretched while they travel throughspace.
D) placing our Galaxy near the center of the Local Group.
E) the differences in temperatures and star formation in old and young galaxies.