Assertion: `alpha, beta and gamma` rays are emitted by disintegration of atomic nuclei of radioactive elements.
Reason : Nuclear fall out is shown by radioactive elements

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion is true but the reason is false
D. If both the assertion and reason are false

Explanation

To analyze the assertion and reason provided in the question, we will break down the statements step by step.

### Step 1: Understand the Assertion
The assertion states that "alpha, beta, and gamma rays are emitted by disintegration of atomic nuclei of radioactive elements."
- **Explanation**: This is true. Radioactive elements undergo nuclear decay, which involves the disintegration of their atomic nuclei. During this process, they emit radiation in the form of alpha particles (helium nuclei), beta particles (electrons or positrons), and gamma rays (high-energy electromagnetic radiation).

### Step 2: Understand the Reason
The reason states that "Nuclear fallout is shown by radioactive elements."
- **Explanation**: This statement is also true. Nuclear fallout refers to the residual radioactive material that falls to the ground after a nuclear explosion or accident. It consists of various radioactive particles, including those emitted by radioactive elements.

### Step 3: Analyze the Relationship
Now, we need to determine if the reason is the correct explanation of the assertion.
- **Explanation**: While both statements are true, the reason does not explain why alpha, beta, and gamma rays are emitted. The emission of these rays is due to the disintegration of atomic nuclei, not directly due to nuclear fallout. Nuclear fallout is a consequence of radioactive decay but does not explain the process of emission itself.

### Conclusion
Based on the analysis:
- **Assertion**: True
- **Reason**: True
- **Relationship**: The reason is not the correct explanation of the assertion.

### Final Answer
Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

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