A dielectric mirror is designed to maximize the reflection of light of vacuum wavelength \(\lambda_0\) incident normally from air (\(n_{\text{air}} = 1.00\)). The mirror consists of two thin coatings deposited on a glass substrate (\(n_s = 1.50\)): layer 1 has index of refraction \(n_1 = 2.00\) and thickness \(t_1 = \dfrac{\lambda_0}{4n_1}\), and layer 2 has index of refraction \(n_2 = 1.25\) and thickness \(t_2 = \dfrac{\lambda_0}{4n_2}\). Light reflects from interface 1 (air to layer 1), interface 2 (layer 1 to layer 2), and interface 3 (layer 2 to substrate).

Which of the following correctly identifies the phase shift upon reflection at interface 2 and the resulting phase relationship among all three reflected waves when they emerge back into the air?