JEE Main Physics question

Two bodies of different masses of 2 kg and 4 kg are moving with velocities of 20 m/s and 10 m/s towards each other due to mutual gravitational attraction. What is the velocity of their centre of mass?

• (A)5 m/s
• (B)6 m/s
• (C)8 m/s
• (D)ZeroCorrect