Sue asked three of her friends after class if they thought the

test they just finished taking was as easy as she thought it was. They all agreed that it was. She was surprised to find out the next day that, although she and her friends had indeed done well, a majority of the class had failed. Why shouldn't Sue have been surprised?
A) Most of the students did not study for the test.
B) She did not use random selection when asking people about the test.
C) Students should have been randomly assigned to take the tests on different days.
D) Her friends shouldn't have expressed their views regarding the test.

Answer: B