(A): A FM signal is less susceptible to noise than an AM signal.
(B) : In FM transmission, the message signal is in the form of frequency variations of carrier waves. During modulation process, the noise gets amplitude modulated.

Options

A. Assertion and reason are true and reason is the correct explanation of assertion
B. Assertion and reason are true but reason is not correct explanation of assertion
C. Assertion is true but reason is false
D. Assertion is false but Reason is true.

Answer

To analyze the given statements (Assertion and Reason) regarding FM and AM signals, let's break it down step by step.

### Step 1: Understand the Assertion
**Assertion (A):** A FM signal is less susceptible to noise than an AM signal.

- **Explanation:** Frequency Modulation (FM) signals are indeed less susceptible to noise compared to Amplitude Modulation (AM) signals. This is because noise typically affects the amplitude of a signal. In AM, the information is encoded in the amplitude of the carrier wave, meaning that any noise that affects amplitude will directly impact the quality of the received signal. In contrast, FM encodes information in the frequency variations of the carrier wave. Thus, even if noise affects the amplitude, it does not significantly impact the frequency variations, allowing FM signals to maintain better integrity in the presence of noise.

### Step 2: Understand the Reason
**Reason (B):** In FM transmission, the message signal is in the form of frequency variations of carrier waves. During the modulation process, the noise gets amplitude modulated.

- **Explanation:** This statement is also true. In FM transmission, the message signal is indeed represented by variations in frequency of the carrier wave. When noise is introduced into the system, it typically affects the amplitude of the signal. However, since FM relies on frequency variations, the core message remains intact despite amplitude fluctuations caused by noise. This is why FM is less affected by noise.

### Step 3: Conclusion
Both the assertion and the reason are true, and the reason correctly explains why the assertion is true. Therefore, the conclusion is that FM signals are less susceptible to noise than AM signals due to the nature of how information is encoded in frequency rather than amplitude.

### Final Answer:
- **Assertion (A)** is true.
- **Reason (B)** is true and explains (A).

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