Problem: A 30-year-old pregnant woman at 15 weeks gestation presents for maternal serum screening. The screen results show an elevated maternal serum alpha-fetoprotein (MSAFP) level and normal human chorionic gonadotropin (hCG), estriol, and inhibin-A. Which of the following abnormalities is most likely to be present in the fetus? Need Assignment Help service? A. Edwards syndrome B. Down syndrome C. Patau syndrome D. Neural tube defect