Why Is It Critical for Women to Ensure They Are

Why is it critical for women to ensure they are receiving adequate amounts of folate or folic acid prior to pregnancy?

A) because it is very difficult to get adequate amounts of folate or folic acid from a typical American diet
B) because the critical period for folic acid begins during the first 3 to 4 weeks of pregnancy,often before a woman knows she is pregnant
C) there is not a need for extra folate or folic acid,as there is not an increased RDA for pregnancy
D) because a deficiency in folate or folic acid can result in maternal weight gain
E) folate or folic acid is not critical until the third trimester of pregnancy