Data Sufficiency — Family Relations Question: How is R related to M? Statements: I. M's brother is the husband of P. II. P is the mother of R's sister.

Introduction / Context: A kinship (blood-relation) Data Sufficiency problem. We must decide if the statements together or individually are enough to fix the relationship between R and M (e.g., nephew/niece, child, sibling, etc.).

Given Data / Assumptions:

• I: M's brother is P's husband.
• II: P is the mother of R's sister (standard assumption: same mother implies P is R's mother).
• Gender of R is not specified, so the answer will be in the form nephew/niece (child of M's brother).

Concept / Approach: Build the family links: if P is married to M's brother and P is R's mother, then R is the child of M's brother. Therefore, R is M's brother's child, i.e., R is M's nephew or niece (depending on R's gender).

Step-by-Step Solution:

Verification / Alternative check: Neither I nor II alone links R to M conclusively. Only together do they establish that R is the child of M's brother.

Why Other Options Are Wrong:

• I alone sufficient: No, links M↔P but not R.
• II alone sufficient: No, identifies R's mother but no link to M.
• Either alone sufficient: False for the same reason.
• Neither sufficient: False because together they are sufficient.

Common Pitfalls: Ignoring that “mother of R's sister” implies “mother of R”; assuming genders not given; misreading “brother of M” versus “brother-in-law of M”.

Final Answer: Both I and II are sufficient.