The energy levels of a hydrogen-like atom are given by the equation \(E_n = -\dfrac{E_0}{n^2}\), where \(E_0\) is a positive constant and \(n\) is the principal quantum number. An electron in the atom transitions from the \(n = 3\) energy level to the \(n = 2\) energy level, emitting a single photon. Which of the following expressions represents the energy of the emitted photon?