Buttress roots are

Options

A. Aerial
B. Undergound
C. Aquatic
D. Horizontal.

Answer

**Step-by-Step Solution:**

1. **Understanding Buttress Roots**: Buttress roots are specialized roots that provide stability and support to certain types of trees, especially in tropical rainforests.

2. **Analyzing the Options**: The question provides four options regarding the nature of buttress roots:
- Aerial
- Underground
- Aquatic
- Horizontal

3. **Identifying the Characteristics**: Buttress roots typically grow above the ground and extend horizontally from the base of the tree. They are designed to support the tree by spreading out and increasing the surface area in contact with the soil.

4. **Eliminating Incorrect Options**:
- **Aerial**: These roots grow above the ground but do not provide the same structural support as buttress roots.
- **Underground**: Buttress roots are not primarily underground; they are visible above the soil.
- **Aquatic**: This option is not applicable as buttress roots are not adapted to grow in water.

5. **Selecting the Correct Option**: The only option that accurately describes the nature of buttress roots is **horizontal**, as they spread out from the trunk and provide mechanical support.

6. **Conclusion**: Therefore, the correct answer is option number four: **horizontal**.

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