Two Masses Collide and Stick Together

Multiple Choice

Two masses collide and stick together.Before the collision one of the masses was at rest.Is there a situation in which the kinetic energy is conserved in such a collision?

A) Yes,if the less massive particle is the one initially at rest.
B) Yes,if the more massive particle is the one initially at rest.
C) Yes,if the two particles have the same mass.
D) No,kinetic energy is always lost is such a collision.