The half-life period of a radio-active element $$X$$ is same as the mean life time of another radioactive element $$Y$$. Initially they have the same number of atoms. Then

A

$$X$$ will decay faster than $$Y$$

B

$$Y$$ will decay faster than $$X$$

C

$$X$$ and $$Y$$ have same decay rate initially

D

$$X$$ and $$Y$$ decay at same rate always.