. 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?
