Distributions of H II regions overlaid with the corresponding spiral arm models. The fuchsia solid line traces the best-fitted Local Arm given by this work (see Section 4.2). The yellow curved line presents the Perseus Arm determined from the perturbed surface density map of H I by Levine et al. (2006). The solid and long-dashed curved lines in the plot indicate the best-fitted Carina/Sagittarius-Carina Arm (thick) and the other arm segments (thin) given by Xu et al. (2023) and Reid et al. (2019), respectively. H II regions and the positions of the Sun and GC are the same as Fig. 6. The overdensity map of evolved stars (blue) is also shown in the plot to make a comparison.