Multicellular organisms are made of a large number of cells, wherein each cell performs a specific function.
Which of the following organisms is not multicellular?

Options

A. Plants
B. Protists
C. Monkey
D. Mushrooms

Answer

To determine which of the following organisms is not multicellular, we need to understand the difference between multicellular and unicellular organisms.

### Step-by-Step Solution:

1. **Understanding Multicellular Organisms**:
- Multicellular organisms are made up of many cells that work together to perform various functions. Each cell in a multicellular organism has a specific role.

2. **Identifying Unicellular Organisms**:
- Unicellular organisms consist of only one cell that carries out all the necessary functions for survival.

3. **Analyzing the Options**:
- We need to look at the given options and identify which one is unicellular. Common examples of unicellular organisms include bacteria, amoeba, and protists.

4. **Evaluating the Options**:
- If the options include organisms like a monkey, mushroom, and protist, we can analyze:
- **Monkey**: Multicellular organism.
- **Mushroom**: Multicellular organism (fungus).
- **Protist**: Typically unicellular (e.g., amoeba).

5. **Conclusion**:
- Based on the analysis, the organism that is not multicellular is the **protist**.

### Final Answer:
The organism that is not multicellular is **protist**.

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