求助英语问题

___is often the case with a new idea, much preliminary activity and optimistic discussion produced no concrete proposals. H:oQ  
A that, B it, C this, D as c{88m/;eP  
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which one is the answer? thanks!

d吧

我感觉C正确

Ｄ，是正确答案

D，感觉是

D AS

确定 D

选B，it是形式主语，真正的主语部分是后半句。

___is often the case with a new idea, much preliminary activity and optimistic discussion produced no concrete proposals.  I}rGx  
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A. 对于一个新的想法，实际情况是大多数预备活动和乐观的讨论不会得出明确的建议。 V*>73I  
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应该是AS