Ratio of D/H obtained through DCN for each region across NGC 253, shown both for the intensity ratio of DCN (2-1)/H¹³CN (2-1) (in blue) and column density ratio (in red). These observations are shown relative to the prestellar (indicated with ‘PS’) and broad (shown with ‘B’) components of G+0.693-0.027 from Colzi et al. (2022) (C+22, shown in green and orange, respectively), the D/H ratio observed in the shock region L1157-B1 by Busquet et al. (2017) (in purple), and the DCN/HCN ratio observed in the LMC by Chin et al. (1996) (in yellow).