What term describes the legally mandated custom of marrying within one's own caste?

Explanation

The correct term for the practice of marrying within a specific caste is 'endogamy.' 'Endogeny' is unrelated to marriage customs. 'Exegesis' refers to critical interpretation, usually of texts. 'Exclusion' means the act of keeping out. 'Exogamy' is the practice of marrying outside one's social group.