Associated Press - in Order to Determine How American Undergraduate

Associated Press - In order to determine how American undergraduate college
Students feel about eliminating spring break in order to finish spring term a week Early, a survey was conducted. Two hundred undergraduate students from the University of Miami (FL) were interviewed. Both of the interviewers hired to conduct The survey were told to interview 25 freshmen, 25 sophomores, 25 juniors, and 25
Seniors. Of the 200 students interviewed, 20% were in favor of the elimination of
Spring break, 70% were opposed, and 10% had no opinion
-Refer to the situation described above; what type of sampling method was used to gather the sample?

A) Simple Random Sampling
B) Stratified Sampling
C) Biased Sampling
D) Convenience Sampling
E) None of the above.