戈尔巴乔夫的改革与苏联的解体有着密切的关系。下列对该改革内容的叙述中，错误的是

A．推行政治多元化，实行多党制

B．政治领域改革失败后被迫转向经济领域改革

C．以“苏维埃主权共和国联盟”代替原先的苏联

D．用“人道的、民主的社会主义”思想代替了“科学社会主义”

Networks can be interconnected by different devices. In the physical layer networks can be connected by (31) or hubs, which just move the bits from one network to an identical network. One layer up we find bridges and switches which operate at data link layer. They can accept (32) , examine the MAC address and forward the frames to a different network while doing minor protocol translation in the process. In network layer, we have routers that can connect two networks. If two networks have (33) network layer, the muter may be able to translate between the packer formats. In the transport layer we find transport gateway, which can interface between two transport connections. Finally, in the application layer, application gateways translate message (34) . As an example, gateways between Internet e-mail and X.400 e-mail must (35) the e-mail message and change various header fields.

（32）是（）

A.frames

B.packets

C.packages

D.cells