Flowering plants have evolved on amazing array of adaptations to achieve pollination. They make use of

Options

A. external agents
B. internal agents
C. both external and internal agents
D. cleistogamy

Answer

To answer the question regarding how flowering plants have evolved adaptations to achieve pollination, we can break down the solution step by step:

### Step-by-Step Solution:

1. **Understanding Pollination**: Pollination is the process by which pollen is transferred from the male anther of a flower to the female stigma. This is crucial for fertilization and reproduction in flowering plants.

2. **Identifying Adaptations**: Flowering plants have developed various adaptations to facilitate this process. These adaptations can be categorized based on the agents involved in pollination.

3. **Evaluating Options**:
- **Option A: External Agents**: This includes agents like wind, water, and animals (insects, birds, etc.) that help in the transfer of pollen from one flower to another.
- **Option B: Internal Agents**: This would imply mechanisms within the flower itself, which are not typically recognized as agents of pollination.
- **Option C: Both**: This suggests a combination of internal and external agents, but since internal agents are not applicable here, this option can be ruled out.
- **Option D: Clistogamy**: This refers to a specific type of self-pollination that occurs in closed flowers, which is not a general adaptation for pollination.

4. **Conclusion**: Given that flowering plants predominantly rely on external agents for pollination (such as wind, water, and animals), the most accurate answer is **Option A: External Agents**.

### Final Answer:
Flowering plants have evolved adaptations to achieve pollination primarily through the use of **external agents** like wind, water, and animals.

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