The nurse is providing preconception counseling. Which supplement should the nurse recommend to help prevent the occurrence of anencephaly?

A. Calcium: Calcium supports bone health and fetal skeletal development but does not prevent neural tube defects like anencephaly. B. Folic acid: Folic acid supplementation before conception and during early pregnancy reduces the risk of neural tube defects, including anencephaly and spina bifida, by supporting proper neural tube closure during embryonic development. C. Vitamin D: Vitamin D is important for calcium absorption and bone health but has no direct effect on the prevention of neural tube defects. D. Iron: Iron is essential for preventing maternal anemia and supporting fetal growth, but it does not prevent anencephaly or other neural tube defects.