All the following sentences have an appositive EXCEPT______A．He behaved himself fairly wel

All the following sentences have an appositive EXCEPT______

A．He behaved himself fairly well when he was at college.

B．Playing football, his only interest in life, has brought him many friends.

C．Most visitors reach Scotland from the south, that is, from England.

D．Her face was very pale, a grayish pallor.

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