Your Muscle Cells Are Able to Express a Different Complement

Multiple Choice

Your muscle cells are able to express a different complement of proteins from your brain cells because

A) they contain different genes.
B) muscles and brains are the vestiges of different symbiotic organisms present in our ancestors.
C) you inherit the genes for your muscles from your father and the genes for your brain from your mother.
D) the expression of muscle-specific genes is regulated by transcription factors not present in brain cells and vice versa.