Modulation is the phenomenon of :

Options

A. superimposing the audio frequency signal over a carrier wave
B. separating the audio frequency signal from the carrier wave
C. separating carrier wave from the modulated wave
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of Modulation:**
- Modulation is a technique used in communication systems to encode information onto a carrier wave. This is essential for transmitting signals over long distances.

2. **Identifying the Components:**
- There are two main components involved in modulation:
- **Modulating Wave:** This is the signal that contains the information we want to transmit (e.g., audio frequency signal).
- **Carrier Wave:** This is a high-frequency wave that carries the modulating wave.

3. **Superimposing Waves:**
- The process of modulation involves superimposing the modulating wave onto the carrier wave. This means that the characteristics of the modulating wave (like its amplitude, frequency, or phase) will modify the carrier wave.

4. **Resultant Modulated Wave:**
- The outcome of this superimposition is a resultant wave known as the modulated wave. The frequency of this modulated wave is the same as that of the carrier wave, but its amplitude varies according to the modulating wave.

5. **Selecting the Correct Option:**
- Given the options, the correct description of modulation is:
- **Option A:** Superimposing the audio frequency signal over a carrier wave.

**Final Answer:**
- Modulation is the phenomenon of superimposing the audio frequency signal over a carrier wave.

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