Which of the following is true of the bystander effect?

A) The larger the crowd, the faster the response.
B) The larger the crowd, the higher the probability of response.
C) The smaller the crowd, the slower the response.
D) The larger the crowd, the lower the probability of response.

The bystander effect states that the presence of others reduces the likelihood of someone intervening in an emergency situation. Therefore, the more people present, the less likely it is that anyone will respond. Option A and C are incorrect because they suggest that a larger or smaller crowd has a direct relationship with response time, but the bystander effect actually refers to the probability of response. Option B is incorrect because a higher probability of response would mean that people are more likely to intervene, which goes against the bystander effect.