单选题 They are at the moment working ______ time to get everything ready for the conference.
【正确答案】 A
【答案解析】[解析] 副词辨析
against time与时间竞争,赶时间,特别花时间;in time及时,适时;on time准时,按时;ahead应是ahead of time提前,提早;此处表:他们此刻正争分夺秒为会议作准备。因此A为答案。