Is this factory ____ you visited last year?

A. that     B. which      C. where     D. the one

Is this factory ________ you visited last year?

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Is this the factory ___ you visited last year?

       A. the one     B. where      C. that          D.which

Is this the factory ___ you visited last year?

A. the one???? B. where????? C. that????????? D.which