Name two layers of Earth's atmosphere and one key characteristic of each.

• A. Troposphere and Stratosphere; Troposphere contains weather and temperature decreases with altitude; Stratosphere contains the ozone layer and temperature increases with altitude.
• B. Exosphere and Ionosphere; Upper layers
• C. Mesosphere and Thermosphere; Both are cooler with altitude
• D. Troposphere and Mesosphere; Weather occurs there and temperature increases

Answer: (A)

Atmospheric layers differ in how temperature changes with height and in distinctive features that define each layer. The lowest layer is where weather happens; as you rise, the air becomes less dense and temperature generally falls, so it cools with altitude. The next major region contains the ozone layer, which absorbs UV radiation from the sun. That energy absorption heats the surrounding air, so temperature increases with altitude in that layer. This pairing shows how a basic meteorological feature (weather) contrasts with a chemical-energy effect (ozone heating).

Other options mix layers or give vague or incorrect characteristics. For example, upper layers like the exosphere and ionosphere are real, but “Upper layers” isn’t a descriptive feature for both, and they’re not paired with clear, matching characteristics like weather or ozone heating. Mesosphere and thermosphere don’t share a consistent temperature trend in the way stated, since the thermosphere actually warms with height while the mesosphere cools. Troposphere and mesosphere would imply weather in the lower layer but misstate the temperature trend in the higher layer.