A : Callus is obtained within 2-3 weeks.
R : Suspension culture grows much faster than callus culture.

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 and 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 false statements, then mark (4)

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Callus is obtained within 2-3 weeks."
- This is true as callus culture involves the growth of an undifferentiated mass of cells that can be induced in a laboratory setting using plant tissue culture techniques.

2. **Understanding the Reason (R)**:
- The reason states that "Suspension culture grows much faster than callus culture."
- This is also true. Suspension cultures consist of single cells or small groups of cells suspended in a liquid medium, which allows for faster growth compared to callus cultures that are typically grown on solid media.

3. **Analyzing the Relationship**:
- While both statements are true, the reason does not directly explain the assertion. The time taken for callus formation (2-3 weeks) is not influenced by the growth rate of suspension cultures. They are two separate observations about different types of plant tissue cultures.

4. **Conclusion**:
- Since both the assertion and reason are true, but the reason does not provide a correct explanation for the assertion, the correct answer is that the assertion is true and the reason is true but not the correct explanation.

### Final Answer:
- The correct option is: Assertion (A) is true, Reason (R) is true, but R is not the correct explanation for A.

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