Which one is not a flightless bird:

Options

A. Struthio
B. Emu
C. Psittacula
D. Cassowary

Answer

To determine which bird is not a flightless bird, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Bird Classifications**: Birds are classified into two main divisions: Ratitae and Carinates.
- **Ratitae**: These are flightless birds. They have wings that are not modified for flight due to their body structure and weight.
- **Carinates**: These are flying birds with wings that are adapted for flight.

2. **Identify the Birds in the Options**: The question provides several options. We need to analyze each one to see if they belong to Ratitae or Carinates.
- **Struthio (Ostrich)**: This is a flightless bird and belongs to Ratitae.
- **Emu**: This is also a flightless bird and belongs to Ratitae.
- **Cetacoola (Parrot)**: This is a flying bird and belongs to Carinates.
- **Cassowary**: This is another flightless bird and belongs to Ratitae.

3. **Determine the Flightless Bird**: From the analysis:
- Struthio, Emu, and Cassowary are all flightless birds.
- Cetacoola (Parrot) is the only bird that can fly.

4. **Conclusion**: The bird that is not a flightless bird is **Cetacoola (Parrot)**.

### Final Answer:
**Cetacoola (Parrot)** is not a flightless bird.

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