The correct answer is D. Endogamous.
Explanation
Endogamous is a term used to refer to the practice of some group of individuals who radically rejects the incorporation of individuals outside their group or community. Also, this refers to an attitude of communities that prevent members of other groups from associating or joining in marriage, reproduction, or other relationships with members of their group.
This practice was very common in antiquity because it allowed power to be kept within the same family or to maintain the purity of a supposed race. So, the correct answer is D. Endogamous.