In meteorology, an air mass is a volume of air defined by its temperature and water vapor content. Air massess cover many hundreds or thousands of miles, and adapt to the surface below them. Which statement incorrectly describes air masses?

a
Continental air masses form over land and are dry as it loses its moisture to the dry land below it.
b
Maritime air masses form over water and become dry as they lose water vapor to the water below it.
c
Polar air masses form far from the equator where air becomes cool as it loses energy to the cold land or water.
d
Tropical air masses form near the equator and the air is warm.