Question

In a certain 2-inputs logic gate, when $A=0, B=0$, output $C=1$. When $A=0, B=1$, output $C=1$. The gate must be

• A. OR
• B. AND
• C. NAND
• D. NOR

Hint:

NAND and NOR are the only basic gates that give 1 for $(0,0)$ input.

Answer 1

The Correct Option is C

Step 1: Concept
Check the truth tables of the given gates for the specific inputs.

Step 2: Analysis
- OR: $0,0 \to 0$ (Wrong) - AND: $0,0 \to 0$ (Wrong) - NOR: $0,0 \to 1$ but $0,1 \to 0$ (Wrong) - NAND: $0,0 \to 1$ and $0,1 \to 1$.

Step 3: Conclusion
The outputs match the NAND gate truth table. Final Answer: (C)