After nine years’hard-work, finally his dream came true.A. at the endB. at the momentC. at

After nine years’hard-work, finally his dream came true.
A. at the end
B. at the moment
C. at once
D. at last

A. at the endB. at the momentC. at once(答案→)D. at last解析：at the end最后，在终点；at the moment此刻，当时；at once 立刻，马上；at last最后，终于。句意：在九年的努力工作之后，他的梦想终于实现了。结合语境可知选D。

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