“泾溪石险人兢慎，终岁不闻倾履人，却是平流无石处，时时闻说有沉沦。”下列成语与材料中这首唐诗蕴含的哲学道理相一致的是                                  

A．声东击西

B．满招损，谦受益

C．掩耳盗铃

D．画蛇添足

In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet.
Open Shortest Path First(OSPF) is a (66) routing algorithm that (67) work done on the OSI IS-IS intradomain routing protocol. This routing, as compared to distance-vector routing, requires (68) processing power. The Dijkstra algorithm is used to calculate (69) OSPF routing table updates only take place when necessary, (70) at regular intervals.

A．distance-vector

B．link-state

C．flow-based

D．selective flooding