Last school year, the student body of a local university consisted of 30% freshmen, 24% sophomores, 26% juniors, and 20% seniors. A sample of 300 students taken from this year's student body showed the following number of students in each classification: freshmen 83, sophomores 68, juniors 85, and seniors 64. The school superintendent is interested in determine whether there has been a significant change in the classification between last school year and this school year. Which of the following is the correct null hypothesis for this problem?

Select one:

a.the classification for this school year is independent of last school year classification

b.the classification for this school year is dependent on last school year classification

c.there is a significant change in the classification between last school year and this school year

d.None of the above is the correct statement