人民法院审理行政案件，可以依据的规范性文件是( )。

A．北京市某区政府发布的政策采购实施办法

B．云南某自治州制定的在本州范围内实施的单行条例

C．国务院对其最终裁决行为的规定

D．人事部发布的在本部门系统内部施行的规定

What is this talk mainly about

A．How historical events affected an art movement.

B．How artists can influence economic conditions.

C．Why a certain art movement failed to become popular.

D．How valuable paintings were lost during wartime.