高科技在医学中应用所产生的伦理正效应集中体现在（）

A.使临床诊断质量不断提高

B.使医学目的及其道德本质得到越来越充分的实现

C.使临床治疗质量不断提高

D.使医务人员必须面对许多医德问题

E.对医务人员的医德素质提出了许多新的要求

Which of the following statements about the economic rent to a natural resource is most accurate（）

A. The entire payment for a non-renewable natural resource is economic rent. 

B. A non-renewable natural resource earns economic rent only if demand for the resource is perfectly inelastic. 

C. The entire payment for a renewable natural resource is economic rent.