ADAU1961: Mono microphone input

Hello. I'm using the ADAU1961 in a product that has a mono microphone input. No differential inputs, or stereo single-ended inputs. How should I go about connecting a mono microphone to the ADAU1961? I'm assuming the microphone input would be connected to one of the Linx/Rinx/Aux inputs, but am unsure if it should be connected to the P or N channel, if it matters. Also unsure what to do with the other P/N channel.

What is the difference between the Aux and R/Lin pairs?