The managers discussed the the plan that they would like to see carried out next year.

参考译文：经理们讨论了他们想要在明年看到被执行/实施的这个计划。

A.carried out   B.carrying out  C.carry out  D.to carry out

解答：以上A为正确答案，需要填过去分词作宾语补足语结构为 see sth done=看见某事被做。 即 see the plan carried out.

以上句子整体语法结构分析如下

The managers【主语】// discussed【谓语动词】// the the plan 【宾语】//that they would like to see carried out next year【定语从句修饰前面名词the plan】

以上定语从句语法结构分析如下

that【关系代词】//  they【主语】//  would like【谓语动词】//  to see carried out next year【宾语】

以上定语从句宾语语法结构分析如下

 to see【不定式】//  //that【关系代词 （作不定式宾语）】// carried out【宾语补足语】//  next year【时间状语】

备注：关系代词that在定语从句作不定式to see的宾语，为了方便提问网友理解，我把关系代词that放在to see后面。关系代词that=the plan