A phylum common to unicellular animals and plants is

Options

A. Monera
B. Plantae
C. Fungi
D. Protista.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a phylum that is common to both unicellular animals and plants. This indicates that we are looking for a classification that includes both types of organisms.

2. **Five Kingdom Classification System**: The classification system proposed by Sir R. H. Whittaker divides living organisms into five kingdoms: Monera, Protista, Mycota (Fungi), Plantae, and Animalia.

3. **Analyzing the Kingdoms**:
- **Monera**: This kingdom includes all prokaryotic organisms (like bacteria), which are not unicellular animals or plants.
- **Protista**: This kingdom includes all unicellular eukaryotic organisms. It encompasses both unicellular animals (like amoeba and paramecium) and unicellular plants (like Chlamydomonas).
- **Mycota (Fungi)**: This kingdom includes fungi, which are multicellular eukaryotes, so it does not fit the criteria.
- **Plantae**: This kingdom consists of multicellular eukaryotic plants, which also does not fit the criteria.
- **Animalia**: This kingdom includes multicellular eukaryotic animals, which again does not fit the criteria.

4. **Conclusion**: The only kingdom that includes both unicellular animals and unicellular plants is **Protista**. Therefore, the answer to the question is **Protista**.

**Final Answer**: The phylum common to unicellular animals and plants is **Protista**.

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