The decay constant $\lambda$ of a radioactive sample is the probability of decay of an atom in unit time. Then,

  • A
    $\lambda$ decreases as atoms become older.
  • B
    $\lambda$ increases as the age of atoms increases.
  • C
    $\lambda$ is independent of the age.
  • D
    Behaviour of $\lambda$ with time depends on the nature of the activity.

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