【题目】Meeting my dear teachers and fellow students after so many years was indeed a warm occasion, ______ I'd strike into my heart forever.
A.that
B.one
C.when
D.what

【答案】B
【解析】考查替代词。句意：多年以后和我亲爱的老师以及同学们的相聚确实是一件温暖的事情，一件让我铭记永久的事。此处one指代前文中的occasion.故选B项。