Open Shortest Path First(OSPF)is a (29) routing algorithm that (30) work done on the OSI IS-IS intradomain routing protocol. This routing, as compared to distance-vector routing, requires (31) processing power. The Dijkstra algorithm is used to calculate (32) OSPF routing table updates only take place when necessary, (33) at regular intervals.

33（）

A．but rather

B．rather too

C．rather than

D．rather that

产业间贸易与产业内贸易相比较，下列说法错误的是（）。

A.第二次世界大战前产业间贸易占主要地位，第二次世界大战后产业内贸易占主要地位

B.第二次世界大战前产业内贸易占主要地位，第二次世界大战后产业间贸易占主要地位

C.产业间贸易是一国进口和出口不同产业商品

D.产业内贸易是一国既出口同时又进口某种类型产品