Clinging roots occure in

Options

A. Screw pine
B. Podostemon
C. Trapa
D. Orchid

Answer

### Step-by-Step Solution:

1. **Understanding Clinging Roots**: Clinging roots are specialized roots that help plants attach themselves to other structures for support. These roots are commonly found in epiphytes, which are plants that grow on other plants.

2. **Identifying the Function**: The primary function of clinging roots is to provide stability and support to the plant, allowing it to grow in a vertical position, often in areas where soil is not available.

3. **Analyzing the Options**: The question provides several options: screw pine, phodostemon, rapa, and orchid. We need to determine which of these options is known to have clinging roots.

4. **Evaluating Each Option**:
- **Screw Pine**: This plant does not have clinging roots. It is primarily known for its aerial roots but not for clinging.
- **Phodostemon**: This is also not known for having clinging roots.
- **Rapa**: This plant does not exhibit clinging roots either.
- **Orchid**: Orchids are well-known for having clinging roots, which help them attach to trees and other surfaces.

5. **Conclusion**: Based on the analysis, the only plant from the options that has clinging roots is the orchid.

### Final Answer:
Clinging roots occur in **orchids**.

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