To my understanding, a high school graduate has already reached a point in his/her life ______ he/she is supposed to make decisions of his/her own.

A．which

B．where

C．how

D．why

施工成本管理的（）是其他各类措施的前提和保障，而且一般不需要增加什么费用，运用得当可以收到良好的效果。

A．组织措施

B．技术措施

C．合同措施

D．经济措施