问题
单项选择题
A team can accomplish much more than the sum of its individual members and yet frequently groups of people are seen to achieve less than () by the individual member working together.
A. could have been accomplished
B. must have been accomplished
C. should be accomplished
D. would be accomplished
答案
参考答案：A
解析：
could have been accomplished表示“本来可以”的意思，暗含一种假设条件。其他选项都不符合题句的逻辑意义。B项must have been accomplished表示肯定推测而不是虚拟；C项should be accomplished表示一般意义的“应该”，也没有虚拟含义；D项would be accomplished虽然是虚拟形式，但没有“本来可以”的意思，所以只有A项为正确答案。