单选题The government is _____&n

单选题 The government is _____ and will take the necessary steps to maintain security and stability.A.on the alertB.out of controlC.on guardD.in vain

A解析　on the alert (=alert; watchful; careful) 警惕，小心：Drivers must be on the alert for traffic signals. (=Drivers must be especially careful to see signals when driving a car.) (司机必须密切注视交通信号。)out of control 失去控制；on guard站岗；in vain 徒劳，无效。

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