Which type of fog forms when warm, moist air moves over a cold surface?

Advection fog occurs when warm, moist air passes over a colder surface, resulting in the cooling of the air to its dew point, where it condenses into fog. This type of fog is commonly seen when warm ocean air moves inland over colder land or when a warm front moves over a colder area. The key aspect of advection fog is the horizontal movement of warm, moist air—known as advection—over a surface that is significantly cooler.

In contrast, radiation fog typically forms on clear nights when the ground cools rapidly, and moisture condenses close to the ground. Ice fog occurs in extremely cold conditions where moisture in the air forms tiny ice crystals. Upslope fog develops when air is forced to rise over a mountain or elevated terrain, causing it to cool and condense. Advection fog is specifically linked to the movement of warm air over a cold surface, making it the correct answer for this question.