In which scenario might a person experience unilineal descent?

Unilineal descent refers to a system of lineage where individuals trace their ancestry through one parent only, either the maternal line or the paternal line. The correct answer indicates that when a person traces their heritage from a single parent's line, they are engaging in unilineal descent. This approach emphasizes connections and inheritance through one side of the family, which can significantly impact social structure, inheritance rights, and cultural practices.

In scenarios where both maternal and paternal ancestry are considered, the approach is more aligned with a bilateral or cognatic descent system, which does not reflect the principles of unilineal descent. Similarly, only considering maternal relatives still centers on one side but not exclusively through one identified lineage as required by unilineal descent practices—it could lead to confusion regarding broader kinship ties. Finally, when extended family kin are considered, it again suggests a more complex acknowledgment of multiple lines, deviating from the clear-cut inheritance and relational structures characteristic of unilineal descent.