Weathering by Thermal Expansion and Contraction Involves All of the Following

Weathering by thermal expansion and contraction involves all of the following factors EXCEPT:

A) the thermal expansion of air within fractures in rocks enlarges the openings.
B) the outside of a large rock experiences more temperature fluctuations than the inside of the rock.
C) the addition of water to the surface of the rock influences the rate of mechanical weathering.
D) different kinds of minerals within a rock expand at different rates when heated.