Callistemon undergoes

Options

A. entomophily
B. hydrophily
C. ornithophily
D. malacophily

Answer

### Step-by-Step Solution:

1. **Identify the Plant**: The question refers to "Callistemon," specifically "Callistemon subulatus," which is commonly known as the bottle brush plant due to the shape of its flowers.

2. **Understand Pollination Types**: The question mentions different types of pollination: entomophily (pollination by insects), hydrophily (pollination by water), ornithophily (pollination by birds), and malacophily (pollination by mollusks).

3. **Focus on Ornithophily**: The transcript specifies that Callistemon undergoes ornithophily, which is the process of pollination by birds. This is significant because it indicates that the flowers attract birds, which feed on the nectar and inadvertently transfer pollen from one flower to another.

4. **Characteristics of Callistemon Flowers**: Callistemon flowers are described as red, spiked, and produced during the summer. These features are attractive to birds, making them suitable for ornithophily.

5. **Conclusion**: Based on the information provided, the correct answer to the question is that Callistemon undergoes ornithophily.

### Final Answer:
Callistemon undergoes **ornithophily**, which is the process of pollination by birds.

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