Integrated intensity (moment 0) maps of all three CO isotopologue emission lines imaged for this analysis: CO (2–1) (left), ¹³CO (2–1) (center), and C¹⁸O (2–1) (left). The horizontal gray lines in the bottom-left corners represent a length scale of 1000 au, and the pink ellipses in the bottom-right corners represent the beam size. Green contours denote the continuum emission (5σ) from the protoplanetary disks. The locations of structures A, B, and C and the nearby source [BHB2007]-2 (hereafter BHB2) are marked on the maps.