回答如下：
conclusion后面的that从句是
同位语从句，不是
宾语从句，也不是
定语从句。这个that从句仅对前面的名词conclusion作进一步解释、说明和补充, conclusion在从句中不作任何成分。英语的定语从句和同位语从句极易混淆，现谈一下它们之间的区别：
引导定语从句的
关系代词或关系副词指代前面的
先行词，在定语从句中要做成分; 而引导同位语从句的连接词、连接代词、连接副词不指代前面的名词，前面的名词在同位语从句中不作任何成分，同位语从句只用来解释、说明、补充前面的名词。例如：
The news that / which he told us is true. ( 定语从句，关系代词which / that指代news, 在定语从句中作宾语。)
The news that Class One won in the match is a great surprise to us. (同位语从句，名词news在同位语从句中不作任何成分。)
I have no idea that you said. (定语从句)
I had no idea that he would come. (同位语从句)
The question that you asked is not easy to answer. (定语从句)
Mary can answer the question when they will start out. (同位语从句)