Cytochrome c is a small protein associated with the inner membrane of the mitochondrion that functions as an essential part of the electron transport chain in aerobic respiration. Cytochrome c is a critical part of the metabolic process of vastly different organisms, from monkeys to fish. Which statement is true regarding the almost universal presence of cytochrome c in living organisms?

a. Animals with cytochrome c share a common ancestor.
b. Cytochrome c is present in Earth's water cycle, through which it is transferred to all organisms.
c. Cytochrome c is transferred directly from parent to offspring during embryonic development.
d. Animals with cytochrome c evolved, eliminating its requirement in aerobic respiration.