Size of grapes increases in application of

Options

A. gibberellins
B. cytokinin
C. auxin
D. all the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the substance that can increase the size of grapes.

2. **Identifying the Substance**: In horticulture, certain plant hormones are known to influence growth and development in plants. One such hormone is gibberellin.

3. **Role of Gibberellin**: Gibberellin is a plant hormone that promotes growth by stimulating cell elongation and division. It is particularly effective in increasing the size of fruits and other plant structures.

4. **Application of Gibberellin**: When gibberellin is applied to grapevines, it enhances the growth of the grape stalks and the grapes themselves, leading to larger fruit sizes.

5. **Examples of Gibberellin Use**: Besides grapes, gibberellin is also used to increase the size of other fruits like apples and crops like sugarcane, where it helps in elongating and improving the shape of the plant.

6. **Conclusion**: Therefore, the application of gibberellin is what increases the size of grapes.

### Final Answer:
The size of grapes increases with the application of gibberellin.

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