Final answer:
The National Library of Medicine is part of the National Institutes of Health (NIH), which is a leading medical research agency within the U.S. Department of Health and Human Services.
Step-by-step explanation:
The National Library of Medicine is part of the National Institutes of Health (NIH), which is a key agency of the U.S. Department of Health and Human Services responsible for biomedical and public health research. The NIH is the nation's premier medical research agency, making significant discoveries that improve health and save lives. Famous for sponsoring research that has earned over 80 Nobel prizes, the NIH continues to advance knowledge in fields including genetics, cancer, aging, and cardiovascular health. The National Library of Medicine plays a crucial role in disseminating medical knowledge and research findings to the public and professionals.