【题目】___ the machine's enormous size, it runs smoothly and noiselessly.
A.For good
B.For ever
C.For all
D.For sure

【答案】C
【解析】句意：尽管这台机器型号很大，但它运行流畅、无噪音。For good永远；B. For ever永远；C. For all尽管；D. For sure确定。根据题意可知选C项。