Suppose Your Local School District Decides to Randomly Test High

Multiple Choice

Suppose your local school district decides to randomly test high school students for attention deficit disorder (ADD) . There are three high schools in the district, each with grades 9-12. The school
Board pools all of the students together and randomly samples 250 students. Is this a simple random sample?

A) No, because we can't guarantee that there are students from each grade in the sample.
B) No, because we can't guarantee that there are students from each school in the sample.
C) Yes, because the students were chosen at random.
D) Yes, because each student is equally likely to be chosen.
E) Yes, because they could have chosen any 250 students from throughout the district.