Answer:
C) tend to maintain social distinctions between groups
Step-by-step explanation:
Endogamy is a marriage practice in which individuals marry from within the limit of a specific ethnic group, religious group or a social group. This type of marriage segregate individuals from other groups and sees them as unsuitable of marriage relationships. An ethnic group that practices endogamy resists the integration or merging with other surrounding groups. This type of marriage could occur as a result difference in religious beliefs or cultural practices.
In most case endogamy does not give room for incest and sees such practice as taboo. In addition, a group that have been practicing endogamous marriage will definitely have a smaller gene pool compared to a group practicing exogamy.