. . . . . . . . operator returns true, if all the sub-conditions are true.

The correct answer is A. AND.

The AND operator returns true if all the sub-conditions are true. For example, the expression A AND B is true if both A and B are true.

The OR operator returns true if any of the sub-conditions are true. For example, the expression A OR B is true if A is

true, or if B is true, or if both A and B are true.

The NOT operator returns the opposite of its operand.

For example, the expression NOT A is true if A is false, and false if A is true.

The NAND operator returns true if all the sub-conditions are false. For example, the expression A NAND B is true if both A and B are false.

I hope this helps! Let me know if you have any other questions.