Câu 123: GMAT Section 2: Quantitative

A and B are integers. The expression (A+1)(B+1) is even. What can be said about A and B?

1. A. They are both even numbers.
2. B. At least one of them is even.
3. C. At least one of them is odd. — đáp án hiện tại
4. D. They are both odd.
5. E. Nothing can be said surly on A and B.