Living Cells Produce Only One Chiral Form of a Biomolecule

Multiple Choice

Living cells produce only one chiral form of a biomolecule because:

A) biomolecules, by definition, can exist as only one chiral form.
B) living cells can only create L isomers.
C) living cells choose to express only the correct isomer.
D) living cells have enzymes that are also chiral.
E) living cells can produce the opposite chiral form only under certain metabolic conditions.