How Do the Luminosities of Main-Sequence Stars Compare with Those

How do the luminosities of main-sequence stars compare with those in luminosity class III?

A) Main-sequence stars are luminosity class II, so all are more luminous than the stars of luminosity class III.
B) Main-sequence stars are luminosity class V, so all are less luminous than the stars of luminosity class III.
C) Main-sequence stars are luminosity class V. This class spans a range of luminosities, most of which are less luminous than stars in luminosity class III, but a few are more luminous than stars in luminosity class III.
D) Main-sequence stars are luminosity class V, so all are more luminous than the stars in luminosity class III.