An object moves along the positive \(x\)-axis from \(x = 0\) to \(x = L\). Its velocity \(v\) as a function of position is given by \(v(x) = v_0\left(1 - \dfrac{x}{L}\right)\), where \(v_0\) is a positive constant. Which of the following best describes the graph of the object's acceleration \(a\) as a function of position \(x\) over the interval \(0 \le x \le L\)?