- ABoth statements together are needed (neither alone is sufficient)
- BEither statement alone is sufficient
- CStatement II alone is sufficient but Statement I alone is not
- DStatement I alone is sufficient but Statement II alone is not
Step-by-Step Solution
From I, A is the paternal grandfather of D; from II, A is the maternal grandfather of D. Each alone fixes A as D's grandfather.
Answer: B) Either statement alone is sufficient