The basis of Protozoa classification is :

Options

A. Measurement
B. Shape
C. Locomotion
D. Number of nuclei

Answer

### Step-by-Step Solution:

1. **Understanding Protozoa Classification**: Protozoa are single-celled organisms that are classified into different groups based on certain characteristics.

2. **Identifying the Groups**: The four main groups of protozoa are:
- **Mastigophora**: These protozoa move using flagella.
- **Sarkodena**: These protozoa use pseudopodia (temporary extensions of their cytoplasm) for movement.
- **Sporozoa**: These protozoa do not have any locomotory organelles and are generally non-motile.
- **Ciliata**: These protozoa use cilia for locomotion.

3. **Analyzing the Options**: The question provides several options regarding the basis of classification for protozoa:
- **Measurement**: This is incorrect as it does not relate to how protozoa are classified.
- **Shape**: This is also incorrect as shape is not the primary basis for classification.
- **Locomotion**: This is correct as it directly relates to how different groups of protozoa move.
- **Number of nuclei**: This is incorrect as it is not a primary classification criterion.

4. **Conclusion**: The correct basis for the classification of protozoa is locomotion, as it differentiates the groups based on their movement mechanisms.

### Final Answer:
The basis of Protozoa classification is **locomotion**.

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