Answer:
Pluralistic ignorance
Step-by-step explanation:
In social psychology, the term pluralistic ignorance refers to a situation in which the members of a group reject a norm internally or think it's wrong or disagree with it but they don't say anything because they assume that the other members accept it and think it's all just fine.
In this example, many members of a fraternity believe that their initiation process is too harsh and dangerous, but they don't say it out loud because they assume that everyone else thinks that the process is just fine. We can see that this is clearly an example of pluralistic ignorance since they don't agree with the situation but they don't say anything because they assume that the other's think it's fine.