A nail is inserted in the trunk of a tree at a height of 1 metre from the ground level. After 3 years the nail will

Options

A. move downwards
B. move upwards
C. remain at the same position
D. move sideways

Explanation

To answer the question regarding the position of the nail inserted in the trunk of a tree at a height of 1 meter after 3 years, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Plant Growth**:
- Plants exhibit two types of growth: primary growth and secondary growth.
- Primary growth occurs at the tips of the plant (apical meristem) and increases the height of the plant.
- Secondary growth occurs in the lateral meristem (cambium) and increases the thickness (girth) of the plant.

2. **Inserting the Nail**:
- A nail is inserted into the trunk of the tree at a height of 1 meter from the ground.

3. **Effects of Primary Growth**:
- Over the course of 3 years, primary growth will occur at the tips of the plant.
- This means that while the overall height of the tree will increase, the specific point where the nail was inserted (1 meter above ground) will not rise because the growth is happening at the apex of the plant.

4. **Effects of Secondary Growth**:
- Secondary growth will increase the girth of the tree but will not affect the height of the nail.
- The nail remains at the same height because secondary growth does not contribute to vertical elongation.

5. **Conclusion**:
- After 3 years, the nail will remain at the same height of 1 meter from the ground, despite the tree growing taller.

### Final Answer:
The nail will remain at the same height of 1 meter from the ground after 3 years.

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