To test a new medicine, each of 300 volunteers was assigned a distinct number from 1 to 300. Next, a calculator was used to simulate drawing 150 balls from among 300 congruent balls. The balls were numbered the same way as the volunteers so that 150 volunteers to receive the new medication would be chosen without bias. The other volunteers received a placebo. Weeks later, the 2 groups were compared. Which of the following phrases best describes the company’s testing?
The correct answer is B.
The company's testing was randomized because the 150 volunteers were chosen without bias. The testing was also an experiment because the results from a control group (the group that received the placebo) and a treatment group (the group that received the new medication) were compared.