Why can frost remain longer on shaded grass than on grass in direct sunlight on a winter morning?

Correct answer: Shaded grass receives less direct solar energy, so its frost may melt more slowly

The correct answer is A. Direct sunlight supplies energy that warms exposed grass and melts its ice crystals. Shaded grass receives less direct solar energy and may warm more slowly, so the frost can persist longer. This does not mean frost always continues forming in the shade.