The following is a list of terms related to Security. After reading it, you are required to find the items equivalent to (与…等同) those given in Chinese in the table below. Then you should put the corresponding letters in the brackets.A air traffic control system I patrolling vehicleB armed police J safety precaution measureC crime prevention K safety control deviceD entry requirement L security command centerE international criminal police organization M security serviceF level of security N security control centerG picket line O security personnelH police station P valid documentsQ security monitoring and controlExamples: ( M ) 保安服务 ( G ) 警戒线1. ( ) 空中交通管制系统 ( ) 安全预防措施2. ( ) 巡逻车 ( ) 武装警察3. ( ) 国际刑警组织 ( ) 有效证件4. ( ) 入境要求 ( ) 安保人员5. ( ) 安全保障级别 ( ) 安全监控