Problem: A caste system differs from a class system because: Need Assignment Help? A) a caste system is an open system of stratification, while a class system is a closed system of stratification. B) it is not possible for an individual to change his or her caste, while a class system allows people to change their class through individual achievement. C) the social mobility in caste systems varies from society to society, while in a class system there is no social mobility. D) a caste system is a less rigid form of social stratification, while a class system is a comparatively more rigid form of social stratification.