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?

This test identifies an Rh incompatibility between the mother and fetus.

It assesses various markers of fetal well-being.

This test assesses fetal lunch maturity.

It is a screening test for spinal defects in the fetus.