An army spokesman stressed that all the soldiers had been ordered _____ clear warning before firing any shots.

A．to issue

B．being issued

C．to have issued

D．to be issued

制造业的传统质量控制程序仅在生产过程的最后阶段对产品进行成批检测，其最大的缺点是：

A．只在生产过程的最后阶段检测所需费用大。
B．有缺陷的产品难以返工。
C．不是100%的有效。
D．未致力于改进整个生产过程。