Cassie is an active member of a vegan group at a Midwestern university that, because it is located in a state famous for pork production, has a long-standing, profitable connection with the meat industry. Cassie and her friends actively protest against the consumption of meat by picketing events like the pregame barbecues, pork-producers meetings held on campus, and even at dorm cafeterias. They widely publicize the health and environmental benefits of being a vegan and consider their beliefs, as vegans, to be morally and ethically superior to those of meat-eaters. For Cassie, her vegan group is best described as a(n)

For Cassie, her vegan group can best be described as an out-group. An out-group simply refers to a social group whereby s particular individual doesn't identify.

In this case, since Cassie is in a state that's famous for its pork production while Cassie and her friends are vegans and actively protest against the consumption of meat. This implies that they're different from every other person and therefore are an out-group.