Which of the following is not an example of natural method of vegetative propagation in plants?

Options

A. Roots in case of sweet potato and Colocasia.
B. Stem in case of garlic and onion.
C. Leaves in case of Bryophyllum and Begonia.
D. Stem in case of Eichhornia and strawberry.

Explanation

To determine which of the following is not an example of a natural method of vegetative propagation in plants, we will analyze each option provided:

1. **Roots in case of Sweet Potato**: Sweet potatoes can indeed propagate through their roots. This is a natural method of vegetative propagation. Therefore, this option is correct.

2. **Collocasia**: Collocasia is known to propagate vegetatively, but it does so through underground stems (corms) rather than roots. Hence, this option is not an example of a natural method of vegetative propagation, making it the correct answer to the question.

3. **Stem in case of Garlic and Onion**: Both garlic and onion propagate vegetatively through their stems (bulbs). This is a natural method of vegetative propagation, so this option is correct.

4. **Brio phylum and Begonia**: These plants can propagate vegetatively through their leaves. This is also a natural method of vegetative propagation, making this option correct.

5. **Stem in case of Acornia and Strawberry**: Both Acornia and Strawberry propagate through their stems (runners). This is a natural method of vegetative propagation, so this option is also correct.

After analyzing all options, the only one that does not represent a natural method of vegetative propagation is the second option regarding Collocasia.

**Final Answer**: The option that is not an example of a natural method of vegetative propagation is the one related to Collocasia.

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