A feature of reproduction that is common to Amoeba, Spirogyra and yeast is that

Options

A. they reproduce asexually
B. they are all unicelluar
C. they reproduce only sexually
D. they are all multicelluar

Explanation

### Step-by-Step Solution:

1. **Identify the Organisms**: The question mentions three organisms: Amoeba, Spirogyra, and Yeast.

2. **Understand Reproduction**: We need to focus on the mode of reproduction common to these organisms. Reproduction can be sexual or asexual.

3. **Analyze Each Organism**:
- **Amoeba**: Reproduces asexually through binary fission.
- **Spirogyra**: Reproduces asexually through fragmentation.
- **Yeast**: Reproduces asexually through budding.

4. **Common Feature**: All three organisms reproduce asexually. This means they do not involve the fusion of gametes and only one parent is involved in the reproduction process.

5. **Eliminate Incorrect Options**:
- Options suggesting they are all unicellular or multicellular can be eliminated since the mode of reproduction does not depend on the number of cells.
- The option stating they reproduce sexually is incorrect as none of these organisms form gametes.

6. **Conclusion**: The common feature of reproduction among Amoeba, Spirogyra, and Yeast is that they all reproduce asexually.

### Final Answer:
The feature of reproduction that is common to Amoeba, Spirogyra, and Yeast is that they all reproduce asexually.

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