Which of the following cannot serve as a vegetative propagule ?

Options

A. `{:("Organism", "Mode of multiplication"), ("Agave, Oxalis"," " "Bulbils"):}`
B. `{:("Organism", "Mode of multiplication"), ("Amoeba, Paramecium"," " "Binary fission"):}`
C. `{:("Organism", "Mode of multiplication"), ("Chlamydomones, Ulothrix"," " "Sporangiospores"):}`
D. `{:("Organism", "Mode of multiplication"), ("Adiantum caudatum"," " "Adventitou buds present at leaf tips"):}`

Explanation

To determine which of the following cannot serve as a vegetative propagule, we need to analyze each option based on their modes of reproduction.

1. **Oxalis**: This plant reproduces through vegetative propagation using structures like bulbs. Bulbs are considered vegetative propagules because they can grow into new plants.

2. **Amoeba and Paramecium**: These organisms reproduce asexually through binary fission. While they do not have traditional vegetative propagules like plants, binary fission is a form of asexual reproduction that leads to the formation of new individuals. However, they are not classified as vegetative propagules.

3. **Chlamydomonas and Eulothoryx**: These organisms reproduce through the formation of zoospores, which are motile spores. While zoospores can lead to the formation of new individuals, they are not considered vegetative propagules because they are not structures that develop directly into new organisms without the need for fertilization.

4. **Adiantum (a type of fern)**: This plant can reproduce through adventitious buds, which are structures that can develop into new plants. Adventitious buds are indeed considered vegetative propagules.

Based on this analysis, the option that cannot serve as a vegetative propagule is **Chlamydomonas and Eulothoryx** because their mode of reproduction involves zoospores, which are not vegetative propagules.

### Final Answer:
**Chlamydomonas and Eulothoryx** cannot serve as vegetative propagules.