The position \(x\) of an object moving along the \(x\)-axis as a function of time \(t\) is modeled by \(x(t) = x_0 \cos(\omega t)\), where \(x_0\) is a positive constant and \(\omega = \dfrac{2\pi}{T}\). The object's motion over one complete period from \(t = 0\) to \(t = T\) is shown in the graph. Which of the following graphs best represents the acceleration \(a\) of the object as a function of time \(t\) over the same interval?