Have you ever heard the theme song of the 29th Olympic Games, Hand in Hand, _____ in Chinese? [ ]

A. sing

B. to sing

C. singing

D. sung

监理工程师协助业主确定工程项目总目标时，应力求做到( )。

A．工期最短

B．整个目标系统优化

C．使项目具有足够的适用性

D．使项目具有良好的经济性