A virtual image larger than the object can be produced by a(a). Concave mirror(b). Convex mirror(c). Plane mirror(d). Concave lens

To solve this question, we need to understand how virtual images are formed by different types of mirrors and lenses.

Concave mirror: A concave mirror can produce a virtual image that is larger than the object under certain conditions. This occurs when the object is placed between the focal point and the mirror. In this case, the reflected rays diverge, and when extended backward, they meet at a point behind the mirror, forming a virtual image that appears larger than the object.

Convex mirror: A convex mirror always forms a virtual image that is smaller than the object. The image appears to be behind the mirror and is always diminished.

Plane mirror: A plane mirror forms a virtual image that is the same size as the object. The image is laterally inverted but not magnified.

Concave lens: A concave lens always forms a virtual image that is smaller than the object. The image appears upright and reduced in size.

Conclusion:
The correct answer is (a) Concave mirror. A concave mirror can produce a virtual image larger than the object when the object is placed between the focal point and the mirror.