Security was such a major concern at the conference that no journalists could approach the

Security was such a major concern at the conference that no journalists could approach the meeting zone without the special pass.
A. commanding
B. issuing
C. producing
D. involving

A. commandingB. issuing(答案→)C. producingD. involving解析：句意：会议上的安全是如此重要关注一个的问题,以至于没有出示专门的通行证的记者是不可能接近会议区。commanding 命令，控制；issuing 发行，分配； producing 生产，出示； involving 涉及，包括。根据句意记者只有出示专门的通行证才能接近会议区。故选C。

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