Which of the following is not a characteristic of the troposphere?

The troposphere is the lowest layer of Earth's atmosphere, extending from the surface up to about 8 to 15 kilometers (5 to 9 miles) high, depending on geographical location. One of the defining characteristics of this layer is that it contains most of the air pressure, which decreases with altitude. Additionally, the troposphere is where almost all weather events occur, such as clouds, rain, and storms, due to the presence of water vapor and other air particles.

Because it is the layer closest to the Earth's surface, it hosts the vast majority of atmospheric phenomena. The uppermost layer of the atmosphere is actually the thermosphere, which lies well above the troposphere, making the claim that the troposphere is the uppermost layer incorrect. The correct answer highlights that the troposphere is not the uppermost atmospheric layer, reinforcing its critical role as the foundational layer for weather and climate systems.