Appeared in: 2025 (2 sets)
OR
If an object in case (i) above is $20\text{ cm}$ from the lens and the screen is $50\text{ cm}$ away from the object, the focal length of the lens used is
(A) $10\text{ cm}$
(B) $12\text{ cm}$
(C) $16\text{ cm}$
(D) $20\text{ cm}$