A lens forms an upright and diminished image of an object when the object is placed at the focal point of the given lens.
Name the lens.

Explanation

To determine the type of lens that forms an upright and diminished image when an object is placed at the focal point, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Lens Types**:
- There are two main types of lenses: convex (converging) lenses and concave (diverging) lenses.
- A convex lens can form both real and virtual images, while a concave lens always forms virtual images.

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