Vernalisation can often be replaced by

Options

A. auxin
B. cytokinins
C. gibberellins
D. ethylene

Explanation

**Step-by-Step Solution:**

1. **Understand Vernalization**: Vernalization is the process by which plants or seeds are exposed to low temperatures for a certain period, which induces flowering. This is particularly important for certain plants that require a cold period to trigger their flowering process.

2. **Identify the Alternative**: The question asks for what can replace vernalization. One of the known alternatives is Gibberellins, which are plant hormones.

3. **Explore the Role of Gibberellins**: Gibberellins play several roles in plant growth and development. They are known to:
- Break dormancy in seeds, allowing them to germinate.
- Promote stem elongation, leading to taller plants.
- Induce flowering in some plants, effectively replacing the need for vernalization.

4. **Conclusion**: Given the properties of Gibberellins, they can effectively replace the need for vernalization in promoting flowering in certain plants. Therefore, the answer to the question is that Vernalization can often be replaced by Gibberellins.

**Final Answer**: Vernalization can often be replaced by Gibberellins.

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