You are at a basketball game and the arena is packed; the crowd is evenly split between fans of the two teams

At one point, the referee makes a call. Half of the fans yell insults; the other half of the fans shout their approval. The event reminds you of the topic of today's lecture in psychology class. What was the likely topic of the lecture?
a) bias
b) experiments
c) psychoanalysis
d) extraneous variables

ANS: a