A Person Can See Well in the Distance,but Cannot Do

Multiple Choice

A person can see well in the distance,but cannot do so at an arm's-length distance.To correct this,lenses that are ________ having a ________ power could be used.

A) thicker at their center than at the edges,positive
B) thicker at their center than at the edges,negative
C) thinner at their center than at the edges,positive
D) thinner at their center than at the edges,negative