ABCD
Polar/Cartesian

[[There is a graph. The Y axis is marked out from 0% to 100%. The X axis is unmarked. A red line starts at 50% and traces out a roughly parabolic trend downwards along the X axis.]]
Certainty that this is a clockwise polar plot, not a Cartesian one, as a function of time.
{{Title text: Protip: Any two-axis graph can be re-labeled 'coordinates of the ants crawling across my screen as a function of time'.}}
Protip: Any two-axis graph can be re-labeled 'coordinates of the ants crawling across my screen as a function of time'.