Select the correct answer from each drop-down menu. Study the graph and then complete the passage.

The graph shows data collected near the Mauna Loa volcano in Hawaii from 1955 to 2015. The data includes atmospheric CO2 levels, seawater CO2 concentrations, and seawater pH readings. If the current trend continues, the seawater near Mauna Loa will likely become due to the changing concentration of in the water.