Exclusive-NOR (XNOR) gate terminology: The statement “The Ex-NOR is sometimes called the equality gate” is ________.

Introduction / Context:
Logic gate nicknames often reflect their truth-table behavior. The exclusive-NOR (XNOR) gate outputs a HIGH when its inputs are equal (both 0 or both 1). Because equality is exactly the condition it detects, XNOR is widely referred to as the “equality gate.” This question verifies recognition of that standard terminology.

Given Data / Assumptions:

• Two-input XNOR considered (extensions to more inputs follow parity-like rules).
• Logic HIGH indicates a match between inputs.
• Standard positive-logic conventions apply.

Concept / Approach:
XNOR is the logical complement of XOR. XOR is HIGH when inputs differ; therefore, XNOR is HIGH when inputs are the same. This is equivalent to a digital equality test for two bits, thus the nickname “equality gate.”

Step-by-Step Solution:

Verification / Alternative check:
Implement equality test using basic gates: (A AND B) OR (not A AND not B) equals XNOR. This composite also returns HIGH when A equals B, reinforcing the equality behavior.

Why Other Options Are Wrong:

• Incorrect: Conflicts with the truth-table definition.
• Ambiguous/only for three-input/only for CMOS: The equality interpretation is independent of logic family and holds for the canonical two-input case.

Common Pitfalls:
Confusing XOR with XNOR; overlooking that “exclusive” in XOR means “one or the other but not both.” Remember: XNOR = equal → HIGH; XOR = different → HIGH.

Final Answer:
Correct