A scientist thinks that a certain chemical is a mutagen. She exposes plant cells to a large amount of this chemical in the laboratory. Which statement best provides evidence that the substance is a mutagen?

A.) The cells die within hours of being exposed to the chemical.
B.) The cells grow more quickly than those that were not exposed to the chemical.
C.) The cells change after being exposed to the chemical, and this change is passed to the next generation of cells.
D.) The cells continue to divide at the same rate as before they were exposed to the chemical.