NDA 2023 Physics question

A 100 g sphere is moving at a speed of 20 m/s and collides with another sphere of mass 50 g. If the second sphere was at rest prior to the collision and the first sphere comes at rest immediately after the collision, considering the collision to be elastic, the speed of the second sphere would be

• (A)10 m/s
• (B)20 m/s
• (C)30 m/s
• (D)40 m/sCorrect