Assertion (A): Convex lens behaves like a simple microscope.
Reason (R): For larger magnifying power, the focal length of convex lens should be small.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

**Assertion (A): Convex lens behaves like a simple microscope.**

1. **Understanding the Assertion**: A convex lens is indeed used in simple microscopes. The primary function of a convex lens is to converge light rays that are coming from an object. When an object is placed between the focal point and the lens, the lens produces a magnified virtual image of the object. This is the principle behind how a simple microscope works.

2. **Conclusion for Assertion**: Therefore, the assertion is true.

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**Reason (R): For larger magnifying power, the focal length of convex lens should be small.**

1. **Understanding the Reason**: The magnifying power (M) of a lens is given by the formula:
\[ M = 1 + \frac{d}{f} \]
where:
- \( M \) = magnification
- \( d \) = least distance of distinct vision (approximately 25 cm for a normal human eye)
- \( f \) = focal length of the lens

2. **Analyzing the Relationship**: From the formula, we can see that magnification is inversely related to the focal length \( f \). This means that if the focal length \( f \) is small, the value of \( M \) (magnification) will be larger.

3. **Conclusion for Reason**: Thus, for a larger magnifying power, it is indeed necessary for the focal length of the convex lens to be small. Therefore, the reason is also true.

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**Final Conclusion**: Both the assertion and the reason are true, and the reason correctly explains the assertion.

### Summary of the Solution:
- Assertion (A) is true: A convex lens behaves like a simple microscope.
- Reason (R) is true: For larger magnifying power, the focal length of the convex lens should be small.
- Both statements are true, and the reason is the correct explanation of the assertion.

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