应答器传送的报文包括级间切换信息
参考答案：对
在护套线配线工程检查、验收的保证项目中，导线严禁有扭绞、死弯、绝缘层破坏和护套断裂等现象，抽查（）处进行验收。
A.5
B.10
C.15
D.20
Linda has two Chinese friends. _______ often talk in Chinese. [ ]
A. Their
B. Them
C. They
