Which of the following is a science of public health?

• A. Epidemiology
• B. Anatomy
• C. Immunology
• D. Physiology

Answer: (A)

The main idea is identifying the field that studies health at the population level to prevent disease. Epidemiology is the science of public health because it focuses on how often diseases occur in groups of people and why—examining distribution (who, where, when) and determinants (causes, risk factors) of health outcomes. This knowledge guides surveillance, outbreak response, and the design of interventions to reduce disease and improve health across communities.

In contrast, anatomy, physiology, and immunology are essential for understanding the structure and function of the human body and its immune responses, usually at the individual level, not specifically aimed at population-wide health strategies.