Sequential circuit is a common logic device whose output values, at a given instant, depend upon its input values and the internal state at that instant, and whose internal state depends upon the (66) preceding input values and the preceding internal state. A sequential circuit can assume a finite number of internal states and may therefore be regarded, from an abstract (67) , as a finite (68) .

Combinational circuit is another logic device whose output values, at any given instant, depend upon the input values at that instant. A combinational circuit is a (69) of a sequential circuit whose internal state is not taken (70) .

（66）处填（）。

A．directly

B．immediately

C．instantly

D．snapshot

协议承诺原则要求银行业金融机构与借款人和其他相关各方通过签订完备的贷款合同等协议文件，规范各方有关行为，调整法律关系，明确权利义务和法律责任。（）