To test if vitamin C actually makes people feel better, a vitamin company decides to run a 5-day study where they give one group of 100 randomly-chosen sick participants vitamin C pills and another group of 100 randomly-chosen sick people fake pills, and monitored yet another group of 100 randomly-chosen sick people who took no pills.

At the end of the 5-day experiment, 90 participants in the vitamin C group reported feeling better. 30 participants in the no-pill group felt better after the 5-day period, and 50 participants in the fake group felt better after the 5-day period.

This study included a 'fake' pill/treatment. What is this sometimes called and why is this a good practice (if possible) in well-designed experiments? Be specific.c

No handwriting plz