Can anyone answer this science question NO LINKS

it is certainly a as clearly a has the greater mass

convex lenses are thicker at the middle. rays of light that pass through the lens are brought closer together (they converge). a convex lens is a converging lens. when parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus.

i need the answer to this too but idk it ; -;