Which of the Following Would Be the Most Suitable Hypothesis

Which of the following would be the most suitable hypothesis for study?

A) The Columbus school district has too many janitors.
B) For learning-disabled students, attending a regular classroom is better than attending a segregated classroom.
C) Solutions to math problems should be taught with computers as well as with paper-and-pencil computation.
D) Nonsense words are forgotten more quickly than meaningful words.
E) Teachers who have had a counseling course will be better teachers than those who have not had a counseling course.