Question

a spiral galaxy containing a significant amount of dark matter will compared to the same galaxy without dark matter. spin slower appear darker spin faster have a higher redshift have a lower redshift

Explanation:

Dark matter contributes to the total mass - energy of a galaxy. It provides additional gravitational pull. This extra gravitational force causes the stars and gas in the spiral galaxy to experience a stronger centripetal force, resulting in a faster spin. Redshift is related to the motion of the galaxy as a whole away from us and not directly to the presence of dark matter. And dark matter does not make the galaxy appear darker in the traditional sense of visible light.

Answer:

C. spin faster