B . because in convex mirror image formed small as campare to object but in concave mirror image formed lager nd also smaller as campare to object

Concave Mirror: Enlarged and Virtual Image
A concave mirror is a reflective surface that curves inward. When an object is placed in front of a concave mirror, the reflected rays converge and form an image. This image can either be smaller or larger than the object, depending on the object's position relative to the mirror.

1. Real and Virtual Images
- Real Image: A real image is formed when the reflected rays actually converge at a point. It can be captured on a screen and is always inverted. Real images are formed when the object is placed beyond the focal point of the mirror.
- Virtual Image: A virtual image is formed when the reflected rays appear to diverge from a point behind the mirror. It cannot be captured on a screen and is always upright. Virtual images are formed when the object is placed within the focal point of the mirror.

2. Enlarged and Diminished Images
- Enlarged Image: An enlarged image is formed when the object is placed beyond the center of curvature of the mirror. In this case, the image is real and inverted, but larger than the object.
- Diminished Image: A diminished image is formed when the object is placed between the center of curvature and the focal point of the mirror. In this case, the image is real and inverted, but smaller than the object.

3. Concave Mirror and Enlarged Image
- A concave mirror can form an enlarged image when the object is placed beyond the center of curvature. The converging rays from the object meet to form a real and inverted image that is larger than the object itself.
- This is possible because the concave mirror focuses the rays and brings them closer together, resulting in a magnified image.

4. Convex Mirror and Diminished Image
- A convex mirror is a reflective surface that curves outward. When an object is placed in front of a convex mirror, the reflected rays diverge and do not meet.
- Convex mirrors always form virtual images that are upright, diminished, and smaller than the object. The image appears to be located behind the mirror.

Conclusion
Based on the above explanations, it can be concluded that a concave mirror can produce an enlarged image when the object is placed beyond the center of curvature. On the other hand, a convex mirror always produces a diminished image that is smaller than the object. Therefore, to get an image larger than the object, a concave mirror is used, and not a convex mirror.