Is this research centre _____ is full of modern equipment you always mention.
A.where
B.that
C.the one that
D.the one where
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C解析这题考查句子成分，this research centre是主语，is是系动词，横线后面是句子，所以句子缺少表语，填the one代替the research centre，另外定语从句中缺少主语所以关系代词用that而且不能省。选C。