Question

A company that manufactures a popular multivitamin wanted to determine whether their multivitamins had any side effects. For its initial study, the company chose 2000 individuals to take one of their multivitamin tablets per day for one year. Scientists from the company surveyed the participants to determine whether they had experienced any side effects. The greatest problem with this procedure is that

Answer 1

4) No control group was used.

Step-by-step explanation:

In order to check the side effects of this multivitamin tablet. It is first important to establish a control group. If the control group does not have the side effects which the treatment group of individuals (those who have taken the multivitamin tablet) have, it shows that the side effect is purely because of the tablet.