Annual rings are distinct in plants growing in

Options

A. Arctic regions
B. Temperate regions
C. Tropical region
D. Grasslands

Answer

**Step-by-Step Solution:**

1. **Understanding Annual Rings**: Annual rings, also known as growth rings, are layers of wood produced by the vascular cambium in plants. They indicate the growth of a tree during a specific year.

2. **Identifying the Regions**: The question provides four options: Arctic regions, temperate regions, tropical regions, and grasslands. We need to determine where annual rings are most distinct.

3. **Characteristics of Temperate Regions**: In temperate regions, there are distinct seasonal changes, notably spring and autumn. These seasonal variations influence the growth patterns of trees.

4. **Vascular Cambium Activity**: In temperate regions, the vascular cambium is more active during the spring when conditions are favorable for growth. This results in the formation of a layer of spring wood, which is typically lighter and less dense.

5. **Autumn Growth**: As the season transitions to autumn, the activity of the vascular cambium decreases, leading to the formation of autumn wood, which is denser and darker.

6. **Formation of Annual Rings**: The contrast between the spring wood and autumn wood creates distinct annual rings. Each complete cycle of spring and autumn growth results in one annual ring.

7. **Conclusion**: Based on the seasonal activity of the vascular cambium and the resulting distinct growth patterns, the correct answer is that annual rings are most distinct in **temperate regions**.

**Final Answer**: Annual rings are distinct in plants growing in **temperate regions**.

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