Major parts of communications systems are:

Options

A. transmitter and receiver
B. receiver and communication channel
C. transmitter and communication channel
D. transmitter, receiver and communication channel

Answer

To solve the question about the major parts of communication systems, we can break it down into a few steps:

### Step 1: Identify the Components of a Communication System
A communication system typically consists of three main components:
1. **Transmitter**: This is the device that converts the message signal into a form suitable for transmission. It modifies the signal for efficient transmission.
2. **Communication Channel**: This is the medium through which the signal travels from the transmitter to the receiver. It can be guided (like cables) or unguided (like air for radio waves).
3. **Receiver**: This device captures the transmitted signal and converts it back into a usable form, allowing the original message to be retrieved.

### Step 2: Analyze the Options Given
Now, let's analyze the options provided in the question:
- **Option A**: Transmitter and Receiver
- **Option B**: Receiver and Communication Channel
- **Option C**: Transmitter and Communication Channel
- **Option D**: Transmitter, Receiver, and Communication Channel

### Step 3: Determine the Correct Answer
From our understanding of the communication system components, we see that the complete system includes all three parts: the transmitter, the communication channel, and the receiver. Therefore, the correct answer is:
- **Option D**: Transmitter, Receiver, and Communication Channel

### Final Answer
The major parts of communication systems are: **Transmitter, Receiver, and Communication Channel** (Option D).

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