Find the odd family relation (gender feature): Pick the option that denotes a male relation, whereas the others denote female relations.

Introduction / Context:
Family-relations classification often turns on gendered kinship terms. When three relations are explicitly female and one is explicitly male (or vice versa), the gender feature provides the clean dividing line for the odd-one-out task.

Given Data / Assumptions:

• Daughter: female child relative to parents.
• Mother: female parent.
• Sister: female sibling.
• Brother: male sibling.

Concept / Approach:
Identify the shared gender characteristic. Here, Daughter, Mother, and Sister clearly indicate female relations, while Brother indicates a male relation. This single binary feature is stable and unambiguous across cultures and languages when the terms are used in their standard sense.

Step-by-Step Solution:

Verification / Alternative check:
Attempt alternative criteria (e.g., generational position). Although “Mother” differs generationally from “Daughter/Sister,” that would still leave two vs one; gender remains the only criterion that separates one from three.

Why Other Options Are Wrong:
They share the explicit female gender attribute, so none of them stands alone by this feature.

Common Pitfalls:
Avoid overcomplicating with extended kinship graphs; the test relies on the obvious gender marking in the words themselves.

Final Answer:
Brother