A dean of residential life wonders if students who live on the top floor of a large dormitory are absent from classes more frequently than students who live on the bottom floor. When students apply to live in the dorm, the dean asks them which floor they would like to live on. The dean randomly selects 10 students who applied for the top floor and 10 students who applied for the bottom floor to be in the experiment. The dean then checks to see if the 10 students who applied and were placed on the top floor were absent more frequently than the 10 students who applied for and were placed on the bottom floor. Has the dean properly used a completely randomized design? A. Yes. Students were randomly selected from those who wished to live on the floors in question.
B. No. Students were not randomly selected to live in the dorm.
C. No. Students should be randomly assigned to classes that start at different times.
D. No. Students should have been randomly assigned to floors and then had their absence rate checked as the year went on.