Difficulty: Medium
Correct Answer: Both I and II are sufficient
Explanation:
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:
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:
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.
Discussion & Comments