Nutation is shown by

Options

A. Root
B. Stem
C. Tendrils
D. Leaves.

Answer

### Step-by-Step Solution:

1. **Understanding Nutation**: Nutation refers to a specific type of movement in plants characterized by a bending or swaying motion. This movement is not uniform and occurs due to the growth patterns of different parts of the plant.

2. **Identifying Plant Parts Involved**: The primary parts of the plant that exhibit nutation are the roots, stems, and leaves. Each of these parts can bend or sway in response to various stimuli, but they do so at different rates.

3. **Mechanism of Nutation**: The bending movement associated with nutation is caused by an unequal rate of growth in different parts of the plant. For example, if one side of a stem grows faster than the other, it will cause the stem to bend towards the slower-growing side.

4. **Prioritizing Plant Parts**: Among the roots, stems, and leaves, nutation is most prominently observed in the roots. This is because roots often grow in response to gravity and moisture, leading to noticeable bending movements.

5. **Conclusion**: Based on the understanding of nutation and its characteristics, we can conclude that the correct answer to the question "Nutation is shown by" is primarily the roots, followed by stems and leaves.

### Final Answer:
Nutation is shown by roots, with stems and leaves also exhibiting this movement but to a lesser extent.

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