Final answer:
The National Healthcareer Association (NHA) regulates phlebotomy certifications, though other agencies like the CDC, OSHA, and FDA play roles in different aspects of phlebotomy practice.
Step-by-step explanation:
The federal agency that regulates phlebotomy certifications is D) National Healthcareer Association (NHA). The NHA provides certification for various healthcare professions, including phlebotomy. It is important to note, however, that while the American Society of Phlebotomy Technicians also issues certificates to individuals who pass their national examination, the actual regulation and guidelines for phlebotomy practice can be under the purview of different agencies such as the Centers for Disease Control and Prevention (CDC) for disease-related protocols, the Occupational Safety and Health Administration (OSHA) for safety practices, and the Food and Drug Administration (FDA) for blood donations and transfusions. The NHA, specifically, addresses the certification aspect that verifies a phlebotomist's qualifications and competency in phlebotomy.