Assertion. On plotting the length of the root against time, a linear curve is obtained
Reason. An elongating root exemplifies arithmetic growth

Options

A. Point out if both are true with reason being correct explanation
B. both true but reason not correct explanation
C. assertion true but reason wrong
D. both are wrong.

Answer

To solve the question regarding the assertion and reason, we will break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that when the length of the root is plotted against time, a linear curve is obtained.
- This implies that the growth of the root is consistent over time, meaning it increases by the same amount in each time interval.

2. **Understanding the Reason**:
- The reason states that an elongating root exemplifies arithmetic growth.
- Arithmetic growth means that the growth occurs at a constant rate, which is characterized by a straight line when graphed.

3. **Analyzing the Relationship**:
- If the root is growing arithmetically, it means that for each unit of time, the root grows by a fixed amount. This is the definition of linear growth.
- Therefore, if the root exhibits arithmetic growth, the plot of root length against time will indeed yield a linear curve.

4. **Conclusion**:
- Both the assertion and the reason are correct. The assertion is true because a linear curve indicates constant growth, and the reason is true because arithmetic growth is defined as growth at a constant rate.
- Thus, the reason correctly explains the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation for the assertion.

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