Review the following draft. Paragraph 1: A contractor searched an old maintenance office for records of a buried water line. A document appeared in an unexpected place. Paragraph 2: In the next paragraph, the writer needs punctuation strong enough to contain the independent thought “the contractor later admitted he had never seen it.” [Sentence to revise: The original blueprint the contractor later admitted he had never seen it was found behind a cabinet.] Which option correctly frames the full-clause interruption “the contractor later admitted he had never seen it” before the main sentence resumes?