Jack is a common person, , I think, that will be found everywhere.A. whom B. whoC. one D.

Jack is a common person, , I think, that will be found everywhere.
A. whom
B. who
C. one
D. he

A. whom B. who(答案→)C. one D. he解析：考查定语从句，one作a common person的同位语，同时又是后面定语从句的先行词，I think作插入语，that在从句中作主语，所以选C。

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