Concept:A concave mirror converges parallel sun rays to a single point.
Explanation:Solar beam consists of rays that are almost parallel when they reach Earth.
A concave mirror reflects these parallel rays inward to meet at its focus.
At the focus, solar energy is concentrated and the heat becomes intense.
This is why concave mirrors are used in solar collectors and solar panels.
Convex mirrors spread rays out, while plane mirrors only reflect without focusing.
Therefore, the concentrating mirror must be concave.
Answer:A. Concave mirror