.Banks accumulated a great deal of knowledge about plants and agriculture. In growing strawberries he went back to the abandoned ______ of spreading straw under the fruit to reduce the necessary amount of watering..

A．custom

B．approach

C．practice

D．principle

为了保证重大项目的建设成功和国民经济系统稳定运行，应从全局的观点，用______的原理来分析其可能带来的各方面的影响，尤其是对区域经济和宏观经济的影响。

A．系统论

B．方法论

C．组织论

D．系统协同论