Two pure samples of radioactive nuclides X and Y have the same initial number of atoms. The half-life of X is \({T_{\frac{1}{2}}}\).

After a time equal to 4 half-lives of X the ratio \(\frac{{{\text{number of atoms of X}}}}{{{\text{number of atoms of Y}}}}\) is \(\frac{1}{8}\).

What is the half-life of Y?

A.     \(0.25{T_{\frac{1}{2}}}\)

B.     \(0.5{T_{\frac{1}{2}}}\)

C.     \(3{T_{\frac{1}{2}}}\)

D.     \(4{T_{\frac{1}{2}}}\)

D