Randomization means: (A) Mixing of cases and controls, (B) Selecting cases, (C) Selecting controls, (D) Vaccine and Erythromycin
Answer is A. Randomization is a statistical procedure by which the study paicipants are allocated into groups usually called study and control groups; to receive or not receive an experimental preventive or therapeutic procedure, maneuver or intervention Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 90