All eukaryotic unicellular organisms belong to 1. Monera . 2. protista .3Fungi. 4.Bacteria.

Options

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

Explanation

To solve the question "All eukaryotic unicellular organisms belong to?" we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Classification System**: Familiarize yourself with the five-kingdom classification system proposed by R.H. Whittaker in 1969. This system categorizes all living organisms into five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.

2. **Identify the Characteristics of Each Kingdom**:
- **Monera**: This kingdom includes all prokaryotic organisms, which are unicellular and lack a defined nucleus.
- **Protista**: This kingdom consists of eukaryotic organisms, which can be unicellular or multicellular. However, it primarily includes unicellular eukaryotes.
- **Fungi**: This kingdom is made up of multicellular eukaryotic organisms, such as molds and mushrooms.
- **Plantae**: This kingdom includes multicellular eukaryotic organisms that are primarily plants.
- **Animalia**: This kingdom consists of multicellular eukaryotic organisms that are animals.

3. **Focus on Unicellular Eukaryotes**: Since the question specifically asks about eukaryotic unicellular organisms, we need to identify which kingdom contains these organisms.

4. **Determine the Correct Kingdom**: From the characteristics outlined, it is clear that the kingdom that includes all eukaryotic unicellular organisms is **Protista**.

5. **Select the Answer**: Therefore, the answer to the question is **2. Protista**.

### Final Answer:
All eukaryotic unicellular organisms belong to **2. Protista**.

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