The air temperature at the tropopause is about minus 80°C over the equator and about minus ……………… over the poles.

Correct option is A

The correct answer is (a) 45°C. The air temperature at the tropopause varies significantly depending on the latitude. Over the equator, where the tropopause is higher, the temperature is approximately -80°C, while over the poles, where the tropopause is lower, the temperature is relatively warmer, around -45°C.
Information Booster:
1. Tropopause marks the boundary between the troposphere and stratosphere.
2. It is higher over the equator (~16-18 km) and lower over the poles (~8-10 km).
3. Temperature decreases with altitude in the troposphere but stabilizes or increases in the stratosphere.
4. Equatorial tropopause temperatures are colder due to stronger vertical convection.
5. Polar tropopause temperatures are warmer due to less intense convection and lower altitude.