Answer: The correct answer is B. "the electromagnetic waves appear more red in color".
Explanation:
Scientists use the Doppler effect to understand the universe by determining the motion of the object.
Red shift: The apparent frequency of light decreases as the source object in space moves away from us. The light is shifted to red end. The apparent frequency decreases and there is increase in the wavelength of the light.
Blue shift: The apparent frequency of light increases as the object in space moves towards us. The light is shifted to blue end. In this case, there is decrease in the wavelength of the light. The frequency of the wave increases.
In the given problem, when the light source moves further away from an observer, the electromagnetic waves appear red in color.
Therefore, the correct option is (B).
