A scientist wants to study the effect of vitamin C on colds. He recruits 100 people with colds and gives the experimental group 1000 mg of vitamin C per day. What would be an appropriate control?

A. Give the control group orange juice every day.
B. Give the control group nothing.
C. Give the control group 1000 mg of another brand of vitamin C per day.
D. Give the control group 2000 mg of vitamin C per day.
E. Give the control group a pill similar to vitamin C but containing sugar (a placebo).


Answer: E

Biology & Microbiology

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