【简答题】A.By copying each other's technology. B.By incorporating features that make their products distinctive. C.By their computers more expensive. D.By their computers run much faster.
【单选题】有以下程序 switch(grade) { case 'A': printf("90~100"); case 'B': printf("80~90"); case 'C': printf("70~80"); case 'D': printf("60~70"); default: printf("Fail!");} 若grade的值为'C',则输出结果是( )。