Jill likes to watch her dad cook. First, he puts liquid raw eggs in a hot pan, and the eggs get stiff. Then, he adds solid cheese to the pan and the cheese gets gooey.

The changes in the eggs and cheese illustrate that
A.
different substances can have different densities.
B.
different substances can have different volumes.
C.
different substances can react differently to heat.
D.
different substances can react differently to light.