下列检索出文献量最少的检索式是() A: AandB B: AorB C: AandBandC D: AorBorC E: AnotB

In the fuel supply system of marine diesel engine, the displacement of the supply pump should be _____ the fuel consumption of the main engine to ensure that the main engine can get enough fuel supply. A: more than B: equal to C: less than D: AorBorC

如果分别以检索词a、b、c在某数据库的关键词字段进入检索都能得到检索结果,结果不为0,下面哪个检索式表示检索结果数最少? A: aanddandc B: aandborc C: aorborc D: aorandc