One of the Consequences of the Collision of Two Galaxies

Multiple Choice

One of the consequences of the collision of two galaxies appears to be

A) a burst of vigorous star birth.
B) a very large explosion, similar to but much larger than a supernova, often known as a superdupernova.
C) almost nothing since stars are widely separated in each galaxy and the probability of star-star collisions is very small.
D) the disappearance of one of them into the central black hole of the other.