技术进步的经济意义直接表现为（）。

A.改变了各产业的要素报酬率

B.产生一系列新兴产业

C.对资本和劳动的节约

D.产业结构调整

Sub-contractors should obey the contractor in information system project. When censoring sub-contractors, the supervisor mostly concerns about （）.

A.Amount of subcontract

B.qualifications and abilities of sub-contractors

C.responsibilities and obligations of sub-contractors

D.the contents of the subcontract