The simplest expression of arithmetic growth is examplified by :-

Options

A. Root elongation at increasing rate
B. Root elongation at constant rate
C. Early zygotic growth
D. All the above

Answer

**Solution:**

To determine the simplest expression of arithmetic growth, we first need to understand what arithmetic growth is.

1. **Definition of Arithmetic Growth**: Arithmetic growth is characterized by a constant rate of growth over time. This means that for each unit of time, the growth increases by a fixed amount. For example, if a plant grows 2 cm every week, after one week it will be 2 cm, after two weeks it will be 4 cm, and so on (2, 4, 6, 8, 10...).

2. **Analyzing the Options**:
- **Root elongation at increasing rate**: This implies that the growth rate is not constant; it increases over time. Therefore, this does not represent arithmetic growth.
- **Root elongation at constant rate**: This indicates that the root grows by a fixed amount over time, which aligns with the definition of arithmetic growth.
- **Early begotic growth**: This refers to the growth of an embryo, which is not consistent and varies over time. Thus, it does not represent arithmetic growth.
- **All of the above**: Since only one of the options correctly describes arithmetic growth, this option is also incorrect.

3. **Conclusion**: The correct answer is "root elongation at constant rate" as it exemplifies the simplest expression of arithmetic growth.

**Final Answer**: Root elongation at constant rate.

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