Question

NAND and NOR gates are called ________.

• A. Bidirectional gates
• B. Unilateral gates
• C. Universal gates
• D. High level logic gates

Hint:

Remember: NAND and NOR = Universal gates. You can make any circuit with just them!

Answer 1

The Correct Option is C

Step 1: What Are Universal Gates?
A universal gate is a logic gate that can be used to implement any Boolean function without needing to use any other type of gate.
Step 2: Why NAND and NOR Are Universal
- Using just NAND gates, one can build AND, OR, and NOT functions.
- Similarly, with NOR gates alone, one can realize all fundamental operations.
- Hence, they are sufficient to design any digital circuit — that's why they're called “universal”.
Step 3: Eliminate Other Options
- (1) Bidirectional → not related to logic types.
- (2) Unilateral → again irrelevant in digital logic.
- (4) High-level logic → no such category officially for gate types.
Conclusion:
Option (3) is correct — NAND and NOR are universal gates.