Due to the thermal effect of the atmosphere () ① Frost mostly appears in cloudy nights in late autumn ② Cloudy days in summer, and the temperature.

A, cloudy nights have strong radiation resistance and high temperature, so frost often appears on sunny nights, which does not meet the meaning of the question;

B, when it is cloudy during the day, the atmospheric clouds and thick atmosphere have a weak weakening effect on solar radiation, so the temperature is high and the cloudy temperature is low, so it is correct;

C, the greenhouse effect can play the role of ground insulation, effectively ensuring the heat on the ground, so it will not affect the survival of human beings, so it does not meet the meaning of the question;

D, the direct heat source of near-surface atmospheric temperature is ground radiation, so the height is too cold, so it is correct.

Comprehensive knowledge shows that ② ④ is correct.

So choose: C.