Which word best describes the practice of testing embryos for genetic defects?

The practice of testing embryos for genetic defects is best described as screening. Screening involves examining embryos to identify any genetic abnormalities or conditions that could lead to diseases or other health issues. This process allows for the early detection of potential problems and provides valuable information for parents and healthcare providers regarding the viability and health of the embryo.

The term "mapping" typically refers to the process of determining the locations of genes or genetic markers on chromosomes, which is different from the actual evaluation or testing of embryos for existing defects. "Profiling" often relates to analyzing an individual's complete genetic makeup or specific traits, but it doesn't specifically address the targeted process of identifying defects in embryos. "Engineering," in this context, would imply modifying or altering the genetic material, rather than simply assessing it for defects. Thus, screening is the most accurate term describing the practice in question.