Primary growth in a plant is caused due to the activities of : -

Options

A. intercalary meristems
B. lateral meristems
C. apical meristems
D. none of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Primary Growth**: Primary growth in plants refers to the increase in length of the plant, which occurs at the tips of roots and shoots. This growth is essential for the plant to extend its reach for light and nutrients.

2. **Identifying Meristems**: Meristems are regions in plants where cells are actively dividing. There are different types of meristems, each responsible for different types of growth:
- **Intercalary Meristem**: Located at the nodes and base of leaves, it contributes to the growth of the internodes (the spaces between nodes).
- **Lateral Meristem**: Responsible for secondary growth, which increases the thickness of stems and roots.
- **Apical Meristem**: Found at the tips of roots and shoots, it is responsible for primary growth.

3. **Evaluating Options**:
- **Intercalary Meristem**: This type contributes to the elongation of the internodes but is not primarily responsible for the overall primary growth of the plant.
- **Lateral Meristem**: This is involved in secondary growth, which thickens the plant structure, not primary growth.
- **Apical Meristem**: This is the correct option as it is directly involved in the primary growth of the plant, facilitating the elongation of roots and shoots.

4. **Conclusion**: After evaluating all the options, the correct answer is that primary growth in a plant is caused due to the activities of the **Apical Meristem**.

**Final Answer**: The correct answer is **Apical Meristem**.

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