下列有关声音的现象中，其本质与其它三个现象不同的是 [ ]

A.在狭小的岩洞中说话，听起来比野外响亮得多

B.在雷雨来临之前，电光一闪即逝，但雷声却隆隆不断

C.岸上人说话，能把水中的鱼吓跑

D.北京天坛的回音壁，能产生奇妙的声学现象

A management domain typically contains a large amount of management information. Each individual item of()information is an instance of a managed object type. The definition of a related set of managed()types is contained in a Management Information Base (MIB) module. Many such MIB modules are defineD. For each managed object type it describes, a MIB()defines not only the semantics and syntax of that managed object type, but also the method of identifying an individual instance so that multiple()of the same managed object type can be distinguisheD. Typically, there are many instances of each managed object()within a management domain.

Each individual item of（）information is an instance of a managed object type.

A．rotation

B．switch

C．management

D．transmission