Ascientist was interested in studying if students political beliefs change as they go through college. two hundred randomly selected students were asked before they entered college if they would consider themselves liberal or conservative. four years later, the same two hundred students were asked if they would consider themselves, liberal or conservative. the scientist decided to perform mcnemar's test. the data is below. what is the null hypothesis? after college before college liberal conservative liberal 80 15 conservative 20 85

a. -0.85 or 0.85

b. -0.39 or 0.39

c. -9.75 or -9.75

d. 1.96 or -1.96