Which of the following is the correct order of chemical reactivity with water according to electrochemical series?

Question

$\begin{array}{1 1}(a)\;K > Mg > Zn > Cu\\(b)\;K > Mg > Cu > Zn\\(c)\;Cu > Zn > K > Mg\\(d)\;Mg > K > Cu > Zn\end{array}$