A star is moving directly towards Earth at a large fraction of the speed of light. How does the light we observe from this star compare to the light received from the same star if it were at rest relative to Earth?

A. The star's light is redder than if it were at rest.
B. The stars apperance is unaffected by its motion.
C. The star appears less luminous than if it were at rest.
D. The star appears more luminous than if it were at rest.