Answer: (A) both concave
The distance from the lens to the focal point is called the focal length. For converging lenses, the focal length is always positive, while diverging lenses always have negative focal lengths. Here the answer is both concave. Both the concave mirror and concave lens have a negative focal length.
Concave mirror
If a hollow sphere is cut into parts and the outer surface of the cut part is painted, then it becomes a mirror with its inner surface as the reflecting surface. This type of mirror is known as a concave mirror.
Concave lens
A concave lens is a lens that diverges a straight light beam from the source to a diminished, upright, virtual image.
