Assertion : The most widely used compound as source of ethylene is ethephon.
Reason : Ethephon hastens fruit ripening in tomatoes and apples and accelerates abscission in stems and leaves.

Options

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

Explanation

To solve the question, we need to analyze the assertion and the reason provided:

### Step 1: Analyze the Assertion
The assertion states: "The most widely used compound as a source of ethylene is ethephon."
- Ethylene is a plant hormone that plays a crucial role in the ripening of fruits and other developmental processes.
- Ethephon is indeed a widely used compound that releases ethylene when it decomposes. Therefore, this assertion is **true**.

### Step 2: Analyze the Reason
The reason states: "Ethephon hastens fruit ripening in tomatoes and apples and accelerates abscission in stems and leaves."
- It is correct that ethephon is used to hasten the ripening of fruits such as tomatoes and apples.
- However, the statement about accelerating abscission (the process where leaves, flowers, or fruits detach from the plant) is partially misleading. Ethephon primarily promotes abscission in flowers and fruits rather than in stems and leaves.
- Therefore, while the first part of the reason is true, the second part is misleading, making the reason **false**.

### Conclusion
- The assertion is true, and the reason is false. Therefore, the correct answer is that the assertion is true, but the reason is false.

### Final Answer
Assertion is true, Reason is false.

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