A repeater is a combination of

Options

A. Receiver
B. Amplifier
C. Transmitter
D. All of these

Answer

To solve the question "A repeater is a combination of," we need to analyze the components involved in the functioning of a repeater in communication systems.

### Step-by-Step Solution:

1. **Understanding the Function of a Repeater**:
A repeater is a device used in communication systems to extend the range of signals. It receives a weak signal, amplifies it, and then retransmits it.

2. **Identifying Components of a Repeater**:
- **Receiver**: The repeater must have a receiver to capture the incoming signal.
- **Amplifier**: After receiving the signal, the repeater amplifies it to strengthen the signal for further transmission.
- **Transmitter**: Finally, the repeater transmits the amplified signal to the next point in the communication system.

3. **Combining the Components**:
Since a repeater performs all three functions—receiving, amplifying, and transmitting—it is a combination of a receiver, amplifier, and transmitter.

4. **Selecting the Correct Option**:
Given the options:
- Option 1: Receiver
- Option 2: Amplifier
- Option 3: Transmitter
- Option 4: All of these

The correct answer is **Option 4: All of these**, as a repeater incorporates all three components.

### Final Answer:
A repeater is a combination of **receiver, amplifier, and transmitter** (Option 4: All of these).

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