Out of the following, universal gate is :-

Options

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

Answer

To solve the question of which gate is a universal gate, we can follow these steps:

### Step 1: Understand the concept of universal gates
Universal gates are logic gates that can be used to create any other type of gate (AND, OR, NOT) through combinations. The two primary universal gates are NAND and NOR.

### Step 2: Identify the options
The question provides four options (A, B, C, D) which are not specified here, but we will assume they include common logic gates such as AND, OR, NOT, and NAND.

### Step 3: Analyze each option
- **NOT gate**: This gate can only invert a single input. It cannot be used to create all other gates.
- **OR gate**: This gate can perform addition of inputs but cannot create all other gates by itself.
- **AND gate**: This gate can perform multiplication of inputs but, like the OR gate, cannot create all other gates alone.
- **NAND gate**: This gate is a combination of AND and NOT. It can be used to create any other gate, making it a universal gate.

### Step 4: Conclude the answer
Since the NAND gate can be used to construct any other logic gate, it is classified as a universal gate. Therefore, the correct answer is the NAND gate.

### Final Answer
The universal gate out of the given options is the **NAND gate**.

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