The cities of Oldtown and Spoonville are the same in area and size of population. Since certain health problems that are caused by crowded living conditions are widespread in Oldtown, such problems must be as widespread in Spoonville. The reasoning in the argument is most vulnerable to criticism on the grounds that the argument ['fails to take into account that having identical overall population density is consistent with great disparity in living conditions', 'fails to distinguish between the size of the total population of a city and the size of the geographic region covered by that city', 'presupposes without warrant that the health problems that are widespread in any particular city cannot be caused by the living conditions in that city', 'fails to indicate whether average life expectancy is lowered as a result of living in crowded conditions']