How Does a MT Air Mass Compare to a CT

Multiple Choice

How does a mT air mass compare to a cT air mass?

A) A mT air mass forms over tropical rainforests and is usually more humid than a cT air mass.
B) A mT air mass forms over an ocean and is usually more humid than a cT air mass.
C) A mT air mass forms over an ocean and is usually less humid than a cT air mass.
D) A mT air mass forms under the equatorial low and is usually less humid than a cT air mass.