Answer:
B. Below Freezing
Explanation:
Frost forms when the dew point is at or below freezing. When the exposed surface (The "Exposed Surface" being what the frost will be formed on) cools by radiating its heat, atmospheric moisture condenses at a rate greater than that at which it can evaporate, resulting in the formation of water droplets. When temperatures are low enough (Below Freezing) , dew takes the form of ice; this form is called frost.
