GKFix MCQ Question

What is the significance of the first focal point (F) of a lens?

• A. It is the point where parallel rays converge after refraction by a convex lens
• B. It is the point where parallel rays *appear* to converge after refraction by a concave lens
• C. It is always located at the optical centre
• D. It is the point where rays passing through it emerge undeviated