P XOR Q is true if exactly one is true. If P is true and Q is false, is P XOR Q true?

• A. No
• B. Yes
• C. Sometimes
• D. Cannot be determined

Answer: (B)

Exclusive or is true exactly when one input is true and the other is false. Here, P is true and Q is false, so exactly one is true. That makes P XOR Q true. So the answer is Yes. The other options don’t fit because they would imply either both are true, both are false, or uncertainty, none of which applies since the truth values are given.