[A] : Cytokinins help in the retention of chloro- phyll and delay senescence in leaves.
[R]: Cytokinins only stimulate root initiation

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

### Step-by-Step Solution:

**Step 1: Analyze the Assertion (A)**
The assertion states that "Cytokinins help in the retention of chlorophyll and delay senescence in leaves."
- Cytokinins are known plant hormones that play a significant role in promoting cell division and growth. They help in the retention of chlorophyll, which is essential for photosynthesis, and delay the aging process (senescence) in leaves. This assertion is true.

**Step 2: Analyze the Reason (R)**
The reason states that "Cytokinins only stimulate root initiation."
- This statement is misleading. While cytokinins do play a role in root development, they are not the primary hormones responsible for root initiation; auxins are primarily responsible for this process. Therefore, this reason is false.

**Step 3: Determine the Relationship Between A and R**
Now we need to evaluate the relationship between the assertion and the reason:
- The assertion is true, but the reason is false. The reason does not correctly explain the assertion, as cytokinins have multiple roles beyond just stimulating root initiation.

**Step 4: Conclusion**
Based on the evaluation:
- The correct conclusion is that the assertion is true, but the reason is false. Therefore, the correct answer would be that the assertion is true and the reason is false.

### Final Answer:
Assertion (A) is true, and Reason (R) is false.

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