Which organisms are not included in the five kingdom system of classification ?

Options

A. Protozoans
B. Viruses
C. Lichens
D. Both (2) & (3)

Answer

To answer the question "Which organisms are not included in the five kingdom system of classification?", we will follow these steps:

### Step 1: Understand the Five Kingdom Classification
The five kingdom classification system, proposed by Robert Whittaker, includes:
1. **Monera**: Prokaryotic organisms (e.g., bacteria).
2. **Protista**: Eukaryotic unicellular organisms (e.g., protozoans).
3. **Fungi**: Eukaryotic organisms that absorb nutrients (e.g., mushrooms).
4. **Plantae**: Eukaryotic organisms that perform photosynthesis (e.g., plants).
5. **Animalia**: Eukaryotic multicellular organisms (e.g., animals).

### Step 2: Identify Organisms Not Included
We need to identify which organisms are not classified within these five kingdoms.

- **Protozoans**: These are classified under the Protista kingdom, so they are included.
- **Viruses**: Viruses do not fit into any of the five kingdoms as they are considered a connecting link between living and non-living entities. They require a host to exhibit characteristics of life.
- **Lichens**: Lichens are symbiotic associations between fungi and algae. They are not classified as a separate kingdom but are considered a combination of the two.

### Step 3: Conclusion
From the analysis:
- **Viruses** and **Lichens** are not included in the five kingdom classification system. Therefore, the correct answer includes both of these options.

### Final Answer
The organisms not included in the five kingdom system of classification are **Viruses** and **Lichens**.