Autumn wood or late wood is formed -

Options

A. In winter
B. In spring
C. Throughout the year
D. in rainy season

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks when autumn wood or late wood is formed. We need to identify the season associated with the formation of this type of wood.

2. **Cambium Activity**: The cambium is a layer of tissue in plants that is responsible for secondary growth. Its activity is crucial in determining the type of wood formed during different seasons.

3. **Types of Wood**: There are two main types of wood formed by the cambium: spring wood (or early wood) and autumn wood (or late wood). The formation of these woods is influenced by the cambium's activity level.

4. **Spring Wood Formation**: Spring wood is formed during the spring season when the cambium is highly active. This results in the production of wider vessels and more xylem and phloem, giving it a lighter color.

5. **Autumn Wood Formation**: In contrast, autumn wood is formed during the autumn and winter seasons when the cambium's activity decreases. This reduced activity leads to the formation of narrower vessels and fewer xylem and phloem elements, resulting in a darker appearance.

6. **Conclusion**: Based on the understanding of cambium activity and the characteristics of the woods formed, we conclude that autumn wood or late wood is formed in the winter season.

**Final Answer**: Autumn wood or late wood is formed in winter.

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