Multiple choice

Which of the following is the lowest part of the atmosphere?

  1. Ionosphere

  2. Mesosphere

  3. Stratosphere

  4. Troposphere

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 75% of the atmosphere's mass and 99% of its water vapour and aerosols.