The Composition of a Planet's Atmosphere Be Measured During a Transit

Multiple Choice

The composition of a planet's atmosphere be measured during a transit by analyzing

A) the excess absorption of starlight at specific wavelengths.
B) the excess emission of starlight at specific wavelengths.
C) the length and depth of the dip in light during the transit.
D) the amplitude and period of the star's motion.
E) the wobble in a star's position on the sky.