Casey performs a survey to determine what students think about the pizza served in the cafeteria. Which is an unbiased representative sample of the population?
A) The last twenty to buy lunch
B) Every tenth student that enters the cafeteria
C) The first 30 students to buy pizzas
D) every fifth student that buys something other than pizza

Question

anonymous · Answer

B; possible biases:
A, the chronically late always eat stale pizza
C, those that like the pizza continue to buy it
D, those that aren't buying it don't llike it