The answer is A because
A commonly used term for tissue-specific stem cells, cells that can give rise to the specialized cells in specific tissues. Includes all stem cells other than pluripotent stem cells such as embryonic and induced pluripotent stem cells.Most embryonic stem cells are derived from embryos that develop from eggs that have been fertilized in vitro—in an in vitro fertilization clinic—and then donated for research purposes with informed consent of the donors. They are not derived from eggs fertilized in a woman's body.
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