Which sentence most accurately describes the layers of Earth's atmosphere?
A. The troposphere and stratosphere together contain about 95% of
the atmosphere's mass.
OB. The troposphere and stratosphere each contain less than 5% of
the atmosphere's mass.
OC. The mesosphere and thermosphere together contain about 95% of
the atmosphere's mass.
D. The stratosphere and mesosphere each contain less than 5% of
the atmosphere's mass.