Suppose a School District Decides to Randomly Test High School

Multiple Choice

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