Which statement about adaptive immunity is true?

• A. It is immediate and non-specific
• B. It does not involve antibodies
• C. It develops over lifetime and can provide memory
• D. It is identical to innate immunity

Answer: (C)

Adaptive immunity is defined by its specificity and its ability to remember past encounters. It develops after exposure to an antigen, with B and T cells expanding to target that specific threat. This process lays down memory cells that persist for years, so future exposures trigger a faster and stronger response, often neutralizing the pathogen before it causes disease. In other words, the hallmark is building a tailored, durable defense rather than a one-time, generic reaction.

That makes the true statement: adaptive immunity develops over lifetime and can provide memory. It hinges on prior exposure and the generation of memory B and T cells, which explain why subsequent encounters are met with a quicker and more robust response, including antibody production by B cells in the humoral arm and targeted cellular responses by T cells.

Consider other ideas: immediate and non-specific describes innate immunity, not adaptive. Saying it does not involve antibodies ignores the central role of antibodies produced by B cells in the adaptive, humoral response. Being identical to innate immunity conflicts with the fundamental differences—adaptive immunity is specific and memory-rich, whereas innate immunity is general and immediate but non-specific.