Which of the following statements BEST reflects the extent to which we can distinguish the effects of genes and the environment on the expression of a complex trait?

A)About 80% of an individual's height is determined by genes and 20% by environment.
B)For identical twins raised in the same environment, height should not differ by more than 20%.
C)In a group of individuals of the same sex, about 80% of the variation in height among individuals is due to genetic differences and 20% is due to environmental differences.
D)If one individual is 60 inches tall and another is 70 inches tall, they differ in about 80% of their genes.
E)None of answer options is correct.