During in vitro fertilization, multiple eggs are extracted and fertilized. The resulting embryos may be screened for their likelihood of a successful pregnancy. The screening can include a method called the preimplantation genetic diagnosis, in which embryos are examined for specific genetic diseases. For example, cystic fibrosis, hemophilia, or chromosome abnormalities are commonly screened against. Once screening is complete, several embryos are selected and implanted into a uterus. What ethical argument supports the use of the embryo screening process?