In data communication, data link is those parts of two data terminal equipments that are controlled by a protocol along with the (71) data circuit, which together enable data (72) . So-called protocol means, in short, a set of rules that determines the behavior of functional units in achieving communication.

Data circuit, however, consists of a pair of (73) transmission channels that provides a means of two-way data transmission. Between data switching exchanges, the data circuit may or may not include data circuit-terminating equipment (DCE), depending on the type of (74) used at the data switching exchange. Between a data station and a data switching exchange or data concentrator, the data circuit includes the DCE at the data station end, and may include equipment (75) to a DCE at the data switching exchange or dam concentrator location.

（72）处填（）。

A．transfer

B．transmission

C．passing

D．delivery

2006年3月5日—14日，第十届全国____________第四次会议在北京人民大会堂举行。全会审查和批准了国民经济和社会发展____________纲要。推动了我国在新的历史起点上朝着全面建设小康社会的目标继续前进。[ ]

A．人民代表大会     第十一个五年规划

B．人民代表大会     第十一个五年计划

C．政治协商会议     第十五个五年规划

D．政治协商会议     第十二个五年规划