On which floor of the building does G stay? (Building has five floors: 1, 2, 3, 4, 5.) I. Only the even-numbered floors are occupied and G does not stay on the second floor. II. G does not stay on an odd-numbered floor.

Introduction / Context:
We must uniquely identify G's floor in a five-floor building. Data Sufficiency asks whether each statement pinpoints a single floor for G without ambiguity.

Given Data / Assumptions:

• I: Only even floors are occupied; G is not on floor 2.
• II: G is on an even floor (i.e., not odd).

Concept / Approach:
Enumerate feasible floors from each statement and check if a unique floor is forced.

Step-by-Step Solution:

Verification / Alternative check:
Check consistency: If only even floors are occupied, II is implied but weaker.

Why Other Options Are Wrong:

• B: II alone leaves two possibilities.
• C: Not either alone; only I suffices.
• D/E: Not applicable since I alone is already sufficient.

Common Pitfalls:
Overlooking “only even-numbered floors are occupied,” which collapses the possibilities.

Final Answer:
Statement I alone is sufficient; Statement II alone is not.