胍类消毒剂的特性是什么？

A. 177
B. 176
C. 175
D. 174

A. 为提高地基抗震强度
B. 水道坏了会使大量的水长期渗透在部分地基上，会使地基强度降低
C. 如果不修复会导致房屋产生裂缝，会降低房屋抗震性能
D. 为了保障人民生命财产

A. it is a layer 2 messaging protocol which maintains vlan configurations across network.
B. it includes an 8-bit field which specifies the priority of a frame.
C. it is used exclusively for tagging vlan frames and dose not address network reconvergence following switched network topology changes.
D. it modifies the 802.3 frame header,and thus requires that the FCS be recomputed.
E. it is a trunking protocol capable of carring untagged frames.