A simple magnifying glass consists of a

Options

A. concave lens
B. convex lens of large focal length
C. convex lens of small focal length
D. plane mirror only

Explanation

### Step-by-Step Solution:

1. **Understand the Components of a Magnifying Glass**:
A magnifying glass is an optical instrument that helps in magnifying small objects. It typically consists of a lens and a handle.

2. **Identify the Type of Lens Used**:
The lens used in a magnifying glass is crucial for its function. There are two main types of lenses: concave and convex.

3. **Determine the Function of the Lens**:
A convex lens is used in a magnifying glass because it converges light rays that are coming from an object. This convergence helps to form a magnified image of the object.

4. **Explain the Image Formation**:
When light rays from an object pass through a convex lens, they converge to form an image. The image formed is larger than the object, which is why we can see details more clearly.

5. **Discuss the Focal Length**:
The focal length of the lens is important for magnification. A magnifying glass typically has a small focal length. This allows the lens to be held close to the eye while still forming a clear image of the object.

6. **Conclude the Type of Lens**:
Since a concave lens diverges light and does not form a magnified image, it cannot be used in a magnifying glass. Therefore, the correct answer is that a simple magnifying glass consists of a **convex lens with a small focal length**.

### Final Answer:
A simple magnifying glass consists of a **convex lens with a small focal length**.

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