Answer: Live attenuated (weakened) vaccine.
- A Killed (inactivated) vaccine preparation
- B Subunit vaccine using isolated antigen
- C Live attenuated (weakened) vaccine
- D Toxoid vaccine made from a toxin
Correct answer: C. Live attenuated (weakened) vaccine
Explanation: MMR (Measles, Mumps, Rubella) is a live attenuated vaccine containing weakened but living viruses. Live vaccines typically produce stronger, longer-lasting immunity as the virus can replicate (but cannot cause disease in healthy people).
An antibody is Y-shaped, with two identical antigen-binding sites at the tips of the variable regions - each shaped to recognise one specific antigen - while the constant (Fc) region at the base is recognised by immune cells to trigger further responses.
Concept context
Innate and adaptive immunity, B cells, T cells, antibodies, vaccines, and immune disorders. Critical for NEET.