Which of the following is not listed as a Boolean operator in the material?

• A. AND
• B. XOR
• C. OR
• D. NOT

Answer: (B)

The concept here is recognizing which operations are treated as basic Boolean operators in the material. The material lists AND, OR, and NOT as the standard building blocks for logic expressions, while XOR is not listed as a basic operator.

XOR (exclusive OR) is true when exactly one of the inputs is true. It isn’t required as a separate primitive because you can create the same behavior using the basic operators: (A AND NOT B) OR (NOT A AND B). This shows XOR can be expressed with AND, OR, and NOT, which is why it isn’t included as a separate listed operator in that material.

For example, if A is true and B is false, XOR is true, and the expression (A AND NOT B) OR (NOT A AND B) evaluates to true as well. If A and B are both true, XOR is false, and the expression evaluates to false too.