Progress so far very good and we are sure that the work will be finished on time.A. wasB.

问题补充：

Progress so far very good and we are sure that the work will be finished on time.

A. was

B. had been

C. has been

D. will be

答案：

A. was

B. had been

(答案→)C. has been

D. will be

解析：根据居中提示词so far可判断用现在完成时。句意为：到目前为止进展很顺利，我们肯定会按时完成。