Which plant hormone causes fruit ripening?
(a) IAA
(b) Cytokinin
(c) Ethylene
(d) GA

Options

A. IAA
B. Cytokinin
C. Ethylene
D. GA

Answer

To determine which plant hormone causes fruit ripening, we can analyze the options provided:

1. **Identify the options**:
- (a) IAA (Indole-3-acetic acid)
- (b) Cytokinin
- (c) Ethylene
- (d) GA (Gibberellic acid)

2. **Understand the role of each hormone**:
- **IAA**: This is primarily involved in cell elongation and differentiation.
- **Cytokinin**: This hormone promotes cell division and can delay aging in plants.
- **Ethylene**: This is known as a gaseous hormone and is specifically associated with the process of fruit ripening.
- **GA**: Gibberellic acid is mainly involved in promoting stem elongation, seed germination, and flowering.

3. **Focus on the question**: The question specifically asks for the hormone that causes fruit ripening.

4. **Recall the function of ethylene**: Ethylene is the only hormone that is directly linked to the ripening of fruits. It is produced naturally by fruits and can also be applied externally to induce ripening.

5. **Conclude with the correct answer**: Based on the information gathered, the hormone that causes fruit ripening is **(c) Ethylene**.

### Final Answer:
The correct answer is (c) Ethylene.

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