Select the correct pair amongst the following

Options

A. Spring wood - light colour , high density
B. Spring wood - dark colour , low density
C. Autumn wood - light colour high density
D. Autumn wood - dark colour , high density .

Answer

To solve the question of selecting the correct pair among the options provided, we need to understand the characteristics of spring wood and autumn wood in the context of secondary growth in dicot stems.

### Step-by-Step Solution:

1. **Understanding Spring Wood**:
- Spring wood, also known as early wood, is formed during the spring season.
- It is characterized by its light color and lower density compared to autumn wood.
- This wood is produced when there is a high availability of water, leading to rapid growth.

2. **Understanding Autumn Wood**:
- Autumn wood, also known as late wood, is formed during the autumn season.
- It is characterized by its dark color and higher density.
- This wood is produced when the growth rate slows down due to reduced water availability and the onset of colder weather.

3. **Evaluating the Options**:
- We need to check the options provided in the question against the characteristics of spring wood and autumn wood.
- Spring wood: Light color, lower density.
- Autumn wood: Dark color, higher density.

4. **Identifying the Correct Pair**:
- Based on the characteristics:
- Spring wood: Light color, lower density (not matching with high density).
- Autumn wood: Dark color, high density (correct).
- Therefore, the correct pair would be autumn wood being dark colored and high density.

5. **Final Answer**:
- The correct pair among the options is that autumn wood is dark colored and of high density.