The correct answer is A. The earth’s radiative equilibrium temperature is the temperature at which the earth is absorbing solar radiation and emitting infrared radiation at equal rates.
Option B is incorrect because the earth radiates energy at maximum intensity at a temperature that is much higher than the radiative equilibrium temperature.
Option C is incorrect because the earth’s average temperature is much higher than the radiative equilibrium temperature. The oceans would not freeze solid if the earth’s temperature were equal to the radiative equilibrium temperature.
Option D is incorrect because the rates of evaporation and condensation on the earth are not in balance at the radiative equilibrium temperature. The earth’s atmosphere is constantly exchanging water vapor with the oceans, and the rates of evaporation and condensation are not constant.