You Notice in the Fall That the Oak Trees on Campus

Multiple Choice

You notice in the fall that the oak trees on campus change color at slightly different times, even though the environment is the same for all the trees. What is the most likely explanation?

A) Natural selection is causing some trees to change.
B) There are different alleles of the gene responsible for color change.
C) The weather changes the genes of the oak trees each year.
D) All the trees have the same genes, but each tree makes different proteins from the genes.