A sealed laboratory container initially contains a pure sample of \(N_0\) radioactive parent nuclei of isotope \(X\). Isotope \(X\) undergoes radioactive decay with a constant half-life \(T_{1/2}\) to form a stable daughter isotope \(Y\), and no daughter nuclei are present at time \(t = 0\). Which of the following graphs best represents the number of parent nuclei \(N_X\) (solid curve) and the number of daughter nuclei \(N_Y\) (dashed curve) in the container as functions of time \(t\)?