Difficulty: Easy
Correct Answer: Correct
Explanation:
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:
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:
Write XOR truth table: 00→0, 01→1, 10→1, 11→0.Complement to get XNOR: 00→1, 01→0, 10→0, 11→1.Observe that outputs are HIGH for equal pairs (00 and 11).Conclude that calling XNOR the equality gate is accurate.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:
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
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