A drug is any substance that

  1. kills viruses only
  2. modifies chemical reactions in the body
  3. is a protein
  4. is made by bacteria
Answer

B) modifies chemical reactions in the body

Definition of a drug. O Level Biology · Topic 12 Disease and Immunity · 12.2 Antibiotics

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