An open-topped cylindrical container of height \(2H\) is exposed to atmospheric pressure \(P_{\text{atm}}\). The container is filled with two immiscible, incompressible liquids: an upper layer of freshwater with uniform density \(\rho_{\text{fresh}}\) extending from depth \(y = 0\) to \(y = H\), and a lower layer of saltwater with uniform density \(\rho_{\text{salt}}\) extending from depth \(y = H\) to \(y = 2H\), where \(\rho_{\text{salt}} > \rho_{\text{fresh}}\). Which of the following best describes the graph of absolute pressure \(P\) as a function of depth \(y\) from \(y = 0\) to \(y = 2H\)?