Which one of the following fits the below description ?
It is a single-celled organism that is a greenish colour and has a cell wall around its cell membrane. It has small infoldings of the cell membrane. It contains genetic material in the cytoplasm which is devoid of any envelope. It has ribosomes for protein synthesis.

Options

A. Type of an algae
B. Type of bacteria
C. Type of fungi
D. Type of virus

Answer

To solve the question, we need to analyze the characteristics of the organism described and match them with the options provided.

### Step-by-Step Solution:

1. **Identify the Characteristics**:
- The organism is single-celled (unicellular).
- It has a greenish color.
- It has a cell wall surrounding its cell membrane.
- It has small infoldings of the cell membrane.
- Its genetic material (DNA or RNA) is present in the cytoplasm and is not enclosed in a nucleus (no nuclear envelope).
- It has ribosomes for protein synthesis.

2. **Determine the Type of Organism**:
- Since it is unicellular and has a cell wall, it could be a type of bacteria or algae.
- The presence of genetic material in the cytoplasm without a nuclear envelope indicates that it is a prokaryotic organism (as opposed to eukaryotic organisms which have a defined nucleus).

3. **Consider the Options**:
- **Bacteria**: Prokaryotic, unicellular, can have a cell wall, and genetic material is present in the cytoplasm. This fits the description.
- **Algae**: Generally eukaryotic and may have a nucleus, so it does not fit the description.
- **Fungi**: Eukaryotic and generally multicellular, does not fit the description.
- **Virus**: Not cellular and does not fit the description as it cannot exist independently outside a host.

4. **Conclusion**:
- The organism that fits all the described characteristics is **Bacteria**.

### Final Answer:
The organism described is **Bacteria**.

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