The mian basis of Classification of Protozoa is

Options

A. Size
B. Shape
C. locomotory device
D. Numbe of nuclei.

Answer

### Step-by-Step Solution:

1. **Understanding the Classification of Protozoa**:
- Protozoa are classified under the kingdom Protista. This is the first step in understanding how they are grouped.

2. **Basis of Classification**:
- The main basis for the classification of protozoa is primarily their mode of locomotion. This means how they move from one place to another.

3. **Locomotory Organelles**:
- Protozoa are categorized based on the type of locomotory organelles or devices they possess. These organelles are crucial for their movement.

4. **Phyla/Classes of Protozoa**:
- Protozoa are divided into four main groups (or phyla/classes):
- **Mastigophora** (or Zooflagellates) - These protozoa move using flagella.
- **Sporozoa** - These are primarily non-motile and are often parasitic.
- **Sarcodina** - These protozoa move using pseudopodia (false feet).
- **Ciliata** - These protozoa move using cilia (tiny hair-like structures).

5. **Conclusion**:
- Therefore, the main basis of classification of protozoa is their locomotory device or organelle.

### Final Answer:
The main basis of classification of Protozoa is **the locomotory device**.

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