Answer:
B
Step-by-step explanation:
A stereotype threat happens in situation where people feel at risk to conform to a particular type of existing stereotype.
The proctor should acknowledge the fact that such stereotype about the math test exists, there is no point in denying it, as Vivian and other students heard about it before. So by stating that 'she has heard that males tend to do better on this test', he confirms the stereotype and doesn't dismiss it as untrue. At the same time, he reassures Vivian that he doesn't think the stereotype is true. This is the best approach as it shows both: admitting the fact that males can do better on the test and giving the female student some degree of safety at the same time.