According to five kingdom system blue green algae belongs to :

Options

A. Metaphyta
B. Monera
C. Protista
D. Algae

Answer

To solve the question regarding the classification of blue-green algae according to the five kingdom system, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Five Kingdom System**: The five kingdom classification system was proposed by Robert Whittaker in 1969. It categorizes living organisms into five distinct kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.

2. **Identify the Characteristics of Blue-Green Algae**: Blue-green algae, also known as cyanobacteria, are photosynthetic organisms. They have characteristics similar to bacteria, such as being prokaryotic (lacking a defined nucleus).

3. **Locate Blue-Green Algae in the Five Kingdoms**: In the five kingdom classification, blue-green algae are classified under the kingdom Monera. This kingdom includes all prokaryotic organisms, which encompasses bacteria and cyanobacteria.

4. **Eliminate Incorrect Options**:
- **Metaphyta**: This term is not used in the five kingdom classification and typically refers to higher plants, which is incorrect for blue-green algae.
- **Protista**: This kingdom includes unicellular eukaryotic organisms, which blue-green algae are not.
- **Algae**: While blue-green algae perform photosynthesis, they are not classified under the kingdom Plantae or as true algae in the five kingdom system.

5. **Conclusion**: Based on the classification, blue-green algae belong to the kingdom Monera.

### Final Answer:
According to the five kingdom system, blue-green algae belong to **Kingdom Monera**.

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