The twinning of tendrils around a support is a good example of

Options

A. Photoperiodism
B. Chemotropism
C. Nastic movements
D. Thigmotropism

Answer

To solve the question regarding the twinning of tendrils around a support, we need to analyze the options provided and understand the concepts involved.

### Step-by-Step Solution:

1. **Identify Tendrils**:
- Tendrils are specialized structures found in climbing plants. They help the plant attach itself to supports for better growth and stability.

2. **Understand the Behavior of Tendrils**:
- When tendrils come into contact with a solid object, they exhibit a coiling behavior. This coiling is a response to the touch of the object, allowing the plant to secure itself.

3. **Examine the Options**:
- **Photoperiodism**: This refers to the plant's response to the length of day and night, primarily in relation to flowering. It is not related to the twining of tendrils.
- **Chemotropism**: This is the movement of a plant in response to a chemical stimulus. It does not apply to the behavior of tendrils.
- **Nastic Movement**: This refers to non-directional movements in response to stimuli. Tendril coiling is directional, so this does not apply.
- **Thigmotropism**: This is the growth or movement of a plant in response to touch or physical contact. This is the correct term for the behavior of tendrils.

4. **Conclusion**:
- The twinning of tendrils around a support is best described by **thigmotropism**, as it involves the plant's response to touch.

### Final Answer:
The twinning of tendrils around a support is a good example of **thigmotropism**.

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