A block of mass \(m\) on a horizontal frictionless surface is attached to an ideal spring of spring constant \(k\). The block is pulled to a displacement of \(x = +A\) from its equilibrium position and released from rest at time \(t = 0\), undergoing simple harmonic motion with a period of oscillation \(T\).

Which of the following graphs best represents the elastic potential energy \(U_s\) (solid line) and the kinetic energy \(K\) (dashed line) of the block-spring system as functions of time \(t\) over the interval from \(t = 0\) to \(t = T\)?