The flightless bird among the following is

Options

A. Columba
B. Neophron
C. Struthio
D. Corvus

Explanation

To determine the flightless bird among the given options (Columba, Neophron, Struthio, and Corvus), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are Columba, Neophron, Struthio, and Corvus.

2. **Research Each Option**:
- **Columba**: This is the scientific name for pigeons. Pigeons are known for their ability to fly.
- **Neophron**: This refers to the Egyptian vulture. Vultures are also capable of flight.
- **Struthio**: This is the scientific name for the ostrich. Ostriches are known to be flightless birds.
- **Corvus**: This is the scientific name for crows. Crows are capable of flying.

3. **Analyze the Findings**:
- From the analysis, Columba and Neophron can fly, while Struthio (ostrich) cannot fly. Corvus (crow) can also fly.

4. **Conclusion**: The only flightless bird among the options is Struthio (ostrich).

### Final Answer:
The flightless bird among the following is **Struthio**.

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