Question

what are convex lenses?
what is a convex lens?
a curved transparent material that refracts light
a flat transparent material that refracts light
an opaque material that reflects light

Explanation:

A convex lens is a curved transparent material. It refracts light. The first option in the given choices correctly describes it as a curved transparent material that refracts light. The second option is incorrect as it says "flat" (convex lenses are curved). The third option is wrong because it mentions an opaque material (lenses are transparent) and reflection (lenses refract, not just reflect).

Answer:

A curved transparent material that refracts light.