Top panel: radius versus mass of the sample of 4465 stars. Red dots indicate the inactive RGBs, green the inactive RCs, and gray the inactive with unknown evolutionary status. Black squares indicate active RGBs, triangles active RCs and × signs active RGs with unknown evolutionary status. Panels b and c: distributions of masses and radii of the inactive and active RG samples as a function of stellar masses (top two panels) and radii (bottom two), according to their evolutionary stages. Empty histograms correspond with the inactive samples, red with the active RGBs, and green with active RCs.