Which of the Following Statements Is True

Which of the following statements is true?

A) Structure/function relationships are evident at the organismal level, but not at the molecular level.
B) Evolution by natural selection led to physiologic adaptation historically, but is not relevant to extant organisms.
C) Homeostasis is the tendency toward relative stability in the internal environment of an organism.
D) Feedback control refers specifically to the homeostatic mechanisms that help organisms stop eating when they're satiated.