Assertion(A): A convex lens of focal length 30 cm can’t be used as a simple microscope in normal setting.
Reason (R): For normal setting, the angular magnification of simple microscope is M=D/f

Explanation

To solve the question, we need to analyze both the Assertion (A) and the Reason (R) provided.

### Step 1: Understand the Assertion
The assertion states that a convex lens with a focal length of 30 cm cannot be used as a simple microscope in normal setting.

- A simple microscope uses a convex lens to magnify small objects.
- The focal length of the lens plays a crucial role in determining how close an object can be placed to the lens while still being in focus.

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