A: Sometimes, some babies have a small tail.
R: This is just a type of mutant variety.

Options

A. If both Assertion `&` Reason are true and the reason is the correct explanation of the assertion. Then mark (1)
B. If both Assertion `&` Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are falses statements, then mark (4)

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that sometimes, some babies have a small tail. This phenomenon is known as atavism, where ancestral traits that were lost during evolution reappear in modern organisms.
- **Conclusion**: The assertion is true.

2. **Understanding the Reason (R)**:
- The reason claims that this occurrence is just a type of mutant variety. Mutations can lead to various traits, but the presence of a small tail in babies is not simply a mutation; it is an expression of a trait that was present in our ancestors.
- **Conclusion**: The reason is false.

3. **Evaluating the Relationship**:
- Since the assertion is true and the reason is false, we need to determine the correct option based on the provided criteria.
- The criteria state that if the assertion is true but the reason is false, we should mark it as option 3.

### Final Answer:
The correct answer is option 3: The assertion is true, but the reason is false.

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