Which Is an Example of Egoism

Which is an example of egoism?

A) Junior high kids who "hook up" with casual friends (because it takes about 20 minutes to heat up the pizza)
B) Choosing to postpone sex until in a committed relationship, even though one sees nothing particularly wrong with casual sex
C) Not having sex because a potential partner may be more emotionally connected than one realizes
D) Treating people with honor because maintaining a good reputation is important