严禁带负荷操作隔离开关，在确认什么情况下方准操作隔离开关？

A. 工作票的生成
B. 工作票的送达
C. 工作票的签发
D. 工作票的接收

A. 业务流程图
B. 决策树
C. 决策表
D. 结构化语言

A. In a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.
B. In an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP field
C. In an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.
D. The differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.
E. The 802.10 standard uses a three bitfield referred to as the user priority bits （PRI） to mark packets as belonging to a specific Co

A. 感觉
B. 概念
C. 判断
D. 推理