- AStatement I alone is sufficient but Statement II alone is not
- BStatement II alone is sufficient but Statement I alone is not
- CEither statement alone is sufficient
- DBoth statements together are needed (neither alone is sufficient)
Step-by-Step Solution
Statement I says X is the sister of Y's mother, so X is Y's maternal aunt (definite). Statement II only makes X a sibling of Y's mother without giving X's gender, so X could be uncle or aunt.
Answer: A) Statement I alone is sufficient but Statement II alone is not