Which of the following form(s) a virtual and erect image for all position of the object?

Options

A. Concave lens
B. Concave mirror
C. Convex mirror
D. Both (a) and (c )

Explanation

To determine which optical devices form a virtual and erect image for all positions of the object, we need to analyze the behavior of different types of mirrors and lenses.

### Step-by-Step Solution:

1. **Understanding Image Formation by Mirrors and Lenses**:
- Mirrors and lenses can form different types of images (real or virtual) depending on the position of the object relative to the focal point and the type of optical device used.

2. **Convex Mirror**:
- A convex mirror is a diverging mirror.
- It always forms a virtual image that is erect and diminished, regardless of the position of the object.
- The image is formed between the pole (the surface of the mirror) and the focus.

3. **Concave Lens**:
- A concave lens is also a diverging lens.
- Similar to the convex mirror, it always forms a virtual image that is erect and diminished for all positions of the object.
- The image is formed on the same side as the object.

4. **Conclusion**:
- Both the convex mirror and the concave lens form virtual and erect images for all positions of the object.
- Therefore, the correct options are:
- A) Convex Mirror
- C) Concave Lens

### Final Answer:
Both A (Convex Mirror) and C (Concave Lens) form virtual and erect images for all positions of the object.

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