Radius responses to adiabatic mass loss of a ﹩3.2\,{M}_{\odot }﹩ star during different evolutionary stages. The initial stellar models are derived from standard evolutionary sequences with a mixing-length convection envelope. Colored lines represent the radius response of the stellar models that are labeled in Figures 1–3. One can notice that the last stellar model terminates unexpectedly, and we address the physical explanation in the last section.