The device which is a combination of a receiver and a transmitter is

Options

A. Amplifier
B. Repeater
C. Transducer
D. Modulator

Explanation

To solve the question, "The device which is a combination of a receiver and a transmitter is," we can follow these steps:

### Step-by-step Solution:

1. **Understanding the Terms**:
- **Transmitter**: A device that sends signals or information from one point to another.
- **Receiver**: A device that receives the signals or information sent by the transmitter.

2. **Combining Functions**:
- The question asks for a device that combines both functions of transmitting and receiving.

3. **Identifying the Device**:
- A device that performs both transmitting and receiving functions is known as a **transceiver**.
- Additionally, in some contexts, a device that amplifies and retransmits signals is called a **repeater**.

4. **Conclusion**:
- Both terms "transceiver" and "repeater" can be used to describe a device that combines the functions of a transmitter and a receiver. However, the most common term used in communication systems for such a device is **transceiver**.

### Final Answer:
The device which is a combination of a receiver and a transmitter is a **transceiver**.

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