Fog is a cloud that has its base at or near the ground.
The answer is letter D. Fog results when atmospheric water vapor condenses to
the extent that the new forms, water droplets or ice crystals, become visible. Saturation
of the air and sufficient condensation nuclei are ordinarily prerequisites for
the formation of fog. One of the great hazards associated with fog is a lack of
visibility.
Fog is a visible weather condition in which the tiny droplets of water present in the atmosphere come together and which forms a thick cloud which lies close to the surface of the ground (land) or above the sea surface. Fog cuts the visibility down to one kilometers, it makes it difficult to observe the things through it. The fog is influenced by several factors such as wind conditions, nearby water bodies, and topography.
Why? This transfer of heat energy away from the ground by the vertical movement of air is called "free convection" or "natural convection." A hot air balloon rises because warmer air is less dense than cool air. (plz brainlyest)