Assertion: Image of an object is of same size by a convex lens. If a glass slab is placed between object and lens, image will become magnified.
Reason: By inserting the slab, image may be real or virtual.

Options

A. If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of the Assertion.
C. If both Assertion is true, but the Reason is false.
D. If both Assertion is false but the Reason is true.

Explanation

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

### Step 1: Understand the Assertion
The assertion states that the image of an object is of the same size when formed by a convex lens if the object is placed at the center of curvature (C) of the lens.

- **Explanation**: When an object is placed at the center of curvature of a convex lens, the image formed is real, inverted, and of the same size as the object.

### Step 2: Analyze the Effect of the Glass Slab
The assertion continues that if a glass slab is placed between the object and the lens, the image will become magnified.

- **Explanation**: Inserting a glass slab introduces a shift in the position of the object relative to the lens. The effective position of the object changes due to the optical path difference created by the slab. The object will appear to move closer to the lens, potentially placing it between the focal point (F) and the center of curvature (C).

### Step 3: Determine the New Image Characteristics
When the object is shifted closer to the lens (between F and C), the lens will produce a magnified image.

- **Explanation**: When the object is between the focal point and the center of curvature, the convex lens produces a virtual, upright, and magnified image.

### Step 4: Understand the Reason
The reason states that by inserting the slab, the image may be real or virtual.

- **Explanation**: This is true because depending on the new position of the object (after the slab is inserted), the image can either be real (if the object is between F and C) or virtual (if the object is between the lens and F).

### Step 5: Conclusion
Both the assertion and the reason are true. However, the reason does not correctly explain the assertion. The assertion specifically refers to the condition of the image size when the object is at C and how the slab changes the object’s position.

### Final Answer
The assertion is true, and the reason is true, but the reason is not the correct explanation for the assertion.