Natural immunity is defined as

• A. Immunity that is acquired solely through vaccination
• B. Immunity that cannot be enhanced by exposure
• C. Immunity that is partly inherited and partly developed through healthy living.
• D. Immunity that lasts only a few days

Answer: (C)

Natural immunity reflects defenses the body has from birth and can be shaped by how we live. Some aspects are inherited through our genetics, setting a baseline for how the immune system responds. At the same time, healthy living—proper nutrition, adequate sleep, regular activity, stress management, and sensible environmental exposures—helps the immune system function well and stay prepared. This combination means immunity is partly inherited and partly developed through healthy living.

Vaccination creates a different kind of immunity (the acquired type), so immunity that is natural isn’t limited to what vaccines provide. Also, natural immunity isn’t guaranteed to be short-lived; while some immediate defenses act quickly and fade, other aspects can confer longer-lasting readiness, and overall durability can be influenced by ongoing health and living conditions.