Which of the following gate is called universal gate

Options

A. OR
B. AND
C. NAND
D. NOT

Answer

To determine which of the following gates is called a universal gate, we need to analyze the options provided: OR gate, AND gate, NAND gate, and NOT gate.

### Step-by-Step Solution:

1. **Understanding Universal Gates**:
- A universal gate is defined as a gate that can be used to create any other type of gate (AND, OR, NOT) through combinations of its own type.

2. **Identifying the Options**:
- The gates provided are:
- OR gate
- AND gate
- NAND gate
- NOT gate

3. **Analyzing Each Gate**:
- **OR Gate**: Cannot be used alone to create AND or NOT gates.
- **AND Gate**: Similarly, cannot be used alone to create OR or NOT gates.
- **NAND Gate**: This gate is a universal gate. By using NAND gates in various configurations, we can create AND, OR, and NOT gates.
- **NOT Gate**: Cannot create AND or OR gates by itself.

4. **Conclusion**:
- Among the options, the **NAND gate** is the universal gate because it can be used to construct the other basic gates (AND, OR, and NOT) through combinations.

### Final Answer:
The universal gate among the given options is the **NAND gate**.

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