All flightless birds comprise a group called

Options

A. Carinatae
B. Aves
C. Odontognathae
D. Ratitae

Answer

**Step-by-Step Solution:**

1. **Understanding the Classification of Birds**: Birds are classified under the class Aves. Within this class, there are two main groups based on their ability to fly.

2. **Identifying the Two Groups**: The first group consists of birds that can fly, known as carinates or winged birds. Examples include crows, parrots, and kites. The second group consists of birds that cannot fly.

3. **Defining Flightless Birds**: The group of flightless birds is specifically referred to as Ratites. These birds have underdeveloped wings and are generally heavier, which prevents them from flying.

4. **Examples of Ratites**: Common examples of Ratites include penguins, emus, and ostriches. These birds are known for their inability to fly.

5. **Conclusion**: Based on the classification and definitions, the correct answer to the question "All flightless birds comprise a group called" is Ratites.

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