Which fog does NOT burn off quickly with sunrise?

Upslope fog forms when moist air is lifted over a topographic feature such as a mountain or hill, causing it to cool and condense into fog. This type of fog is often associated with stable atmospheric conditions and can persist for an extended period, especially when there is continued lift and moisture supply. Unlike radiation fog, which typically forms during clear nights and dissipates quickly with the heating effect of the sun, upslope fog is more resilient to warming temperatures due to its formation mechanism. Thus, it does not burn off quickly with sunrise, making it the correct choice for this question.

Radiation fog, steam fog, and ice fog all have characteristics that allow them to dissipate more rapidly when the sun rises and temperatures increase. For example, radiation fog often forms during the night under clear skies and burns off quickly in the morning as the ground heats up. Steam fog typically occurs when cool air moves over warmer water, and although it can last a bit longer, it also tends to dissipate with warming. Ice fog occurs in extremely cold conditions, primarily in polar regions, but its presence is usually tied to stable, cold weather systems rather than the warming influence of the sun.