Question

A body of mass m, moving at velocity v, collides with a stationary body of the same mass and
sticks to it.
Which row describes the momentum and kinetic energy of the two bodies after the collision?
[The answer is A, but please do explain the proper calculation method achieving such answer]

Answer 1

Here..

Answer 2

Since the collision is inelastic thus the momentum is conserved before and after. And since the bodies have equal masses, they half-en out because now the mass of the moving body is doubled.
Perfect, thanks!