A vaccine contains

  1. antibiotics
  2. antibodies from another person
  3. white blood cells
  4. weakened pathogens or their antigens
Answer

D) weakened pathogens or their antigens

Vaccines stimulate an immune response. O Level Biology · Topic 12 Disease and Immunity · 12.3 Immunity

Biology MCQ · More O Level Biology: Disease and Immunity MCQs · Practise