Reference groups are: $($page $111)$

a$.$ groups people join to enhance their likelihoods of meeting one or more goals

b$.$ groups people join for the sake of the social relationships they provide

c$.$ groups that serve as indicators of status because they restrict membership to certain types of individuals

d$.$ groups to which people compare themselves when evaluating their personal characteristics and experiences

e$.$ groups people belong to which serve as the basis for identity