A body initially at rest, breaks up into two pieces of masses 2 M and 3 M respectively, together having a total kinetic energy E. The piece of mass 2 M, after breaking up, has a kinetic energy :

A

$$\frac{2E}{5}$$

B

$$\frac{E}{2}$$

C

$$\frac{E}{5}$$

D

$$\frac{3E}{5}$$