Two Stars Have the Same Luminosity (Or Absolute Magnitude)

Multiple Choice

Two stars have the same luminosity (or absolute magnitude) .One star is spectral class F and the other is spectral class K.From this information,we know that the:

A) K-type star is larger than the B-type star.
B) B-type star is larger than the K-type star.
C) B-type star is hotter but can be larger, smaller, or the same size as the K-type star.
D) K-type star is hotter but can be larger, smaller, or the same size as the B-type star.