About one in every 33 babies is born with a birth defect. Not all birth defects can be prevented, but a woman can take steps to increase her own chance of having a baby with the best health possible. To avoid the possibility of birth defects, pregnant women should AVOID exposure to all but one of these. That is

A)
drug use.

B)
alcohol use.

C)
folic acid.

D)
cigarette smoking.