Write the following set in the set-builder form $D=\{2,4,6.......\}$

Question

$\begin{array}{1 1}(A)\;D=\{\text{x : x is an even natural number}\}\\(B)\;D=\{\text{x : x is an odd natural number}\}\\(C)\;D=\{\text{x : x is an integer}\}\\(D)\;\text{None of these}\end{array} $