- AStatement I alone is sufficient but Statement II alone is not
- BEither statement alone is sufficient
- CBoth statements together are needed (neither alone is sufficient)
- DStatement II alone is sufficient but Statement I alone is not
Step-by-Step Solution
From I alone X could be Y's father or uncle. II says the paternal grandfather has only one child (Y's father); combined with I, the son X must be that only child, so X is Y's father.
Answer: C) Both statements together are needed (neither alone is sufficient)