Prenatal Diagnosis Techniques, Such as Amniocentesis and Chorionic Villus Sampling

Prenatal diagnosis techniques, such as amniocentesis and chorionic villus sampling, remove cells produced by the embryo. These cells are then used ____.

A) to treat diseases
B) for implantation to produce pregnancy
C) to develop embryonic stem cells
D) to test for the presence of mutant alleles or chromosomal alterations
E) for cloning