[A]: Heritable changes are also called mutations.
[R]: Mutations are sudden change in chromosomal DNA.

i) If both A and R are true and R is the correct explanation of A
ii) If both A and R are true but R is not the correct explanation of A
iii) If A is true and R is false
iv) If both A and R are false

Options

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

Answer

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

### Step-by-Step Solution:

1. **Understanding Assertion (A)**:
- The assertion states that "Heritable changes are also called mutations."
- This is true because mutations are indeed changes in the genetic material that can be passed down from one generation to the next.

2. **Understanding Reason (R)**:
- The reason states that "Mutations are sudden changes in chromosomal DNA."
- This is also true. Mutations can occur suddenly due to various factors, such as environmental influences or errors during DNA replication.

3. **Evaluating the Relationship**:
- Now, we need to determine if the reason (R) correctly explains the assertion (A).
- Since mutations are defined as heritable changes and the reason explains that these changes are sudden alterations in DNA, it logically follows that the reason supports the assertion.

4. **Conclusion**:
- Both A and R are true, and R provides the correct explanation for A.
- Therefore, the correct answer is option i) If both A and R are true and R is the correct explanation of A.

### Final Answer:
i) If both A and R are true and R is the correct explanation of A.

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