A nurse is caring for a client who is scheduled for a maternal serum alpha-fetoprotein test at 15 weeks of gestation. The nurse provides which of the following explanations about this test to the client?

A. Rh incompatibility is assessed using the indirect Coombs test, not maternal serum alpha-fetoprotein (MSAFP). B. While some maternal serum tests assess multiple markers (quad screen), MSAFP specifically screens for neural tube defects, not overall fetal well-being. C. Fetal lung maturity is typically evaluated using amniotic fluid tests such as lecithin/sphingomyelin ratio, not MSAFP. D. Maternal serum alpha-fetoprotein (MSAFP) is produced by the fetal liver and is measured in the mother’s blood; elevated levels can indicate neural tube defects (e.g., spina bifida or anencephaly), making this a screening tool for spinal defects in the fetus.