- ABoth statements together are needed (neither alone is sufficient)
- BStatement I alone is sufficient but Statement II alone is not
- CStatement II alone is sufficient but Statement I alone is not
- DEither statement alone is sufficient
Step-by-Step Solution
I says A is D's brother but leaves D's gender open. II fixes D as a female child of A's mother, so D is A's sister.
Answer: C) Statement II alone is sufficient but Statement I alone is not