GKFix MCQ Question

If the power of a lens is +4.0 D, what does this mean for its focal length and type?

• A. It is a concave lens with a focal length of -0.25 meters
• B. It is a convex lens with a focal length of +0.25 meters
• C. It is a convex lens with a focal length of -0.25 meters
• D. It is a concave lens with a focal length of +0.25 meters