Improvements in Quality of Medical Procedures Often Mean That Cost

Improvements in quality of medical procedures often mean that cost per unit of output decreases, quality of life is improved; however, total costs to society increase. This seeming paradox

A) cannot be explained adequately by economists at this time. More empirical study is needed.
B) is due to economies of scale.
C) is the result of diseconomies of scale.
D) is explained by the fact that more people will demand the treatment if it increases life expectancy or quality of life.
E) is due to the law of diminishing marginal returns.