Final answer:
The science of preserving and protecting health is known as hygiene, which refers to practices like regular bathing, hand washing, and vaccinations to maintain health and prevent diseases.
Step-by-step explanation:
The science of preserving and protecting health is called hygiene. This term refers to practices, habits, and environmental factors aimed at maintaining good health and preventing disease. Hygiene encompasses a variety of practices including regular bathing, hand washing, and dental care, as well as broader public health measures such as vaccinations and public health education. Good hygiene prevents the spread of illnesses by protecting the body against bacteria, fungi, and other pathogens. Furthermore, concepts like prophylaxis underline the importance of methodologies and practices such as vaccination to prevent the emergence and spread of diseases before they occur.