The fact came up      （）   specific speech sounds are recognized by babies as young as 6 months old.

题目解析[填写题目解析]： 题目：The fact came up （） specific speech sounds are recognized by babies as young as 6 months old. A.what B.which C.that D.whose 答案：C 解析：在这个句子中，"The fact"（这个事实）是主语，"came up"（出现，被提及）是谓语动词。我们需要选择一个合适的连接词来引导后面的从句。正确的答案是C选项 "that"，因为在这种情况下，我们使用"that"引导宾语从句，说明"specific speech sounds are recognized by babies as young as 6 months old"是"the fact"的内容。