题目

下列有关显微镜操作的说法，正确的是 ( )A. 高倍镜下细胞质流向是逆时针的，则细胞中细胞质流向应是顺时针的B. 为观察低倍视野中位于左下方的细胞，应将装片向右上方移动，再换用高倍镜C. 用显微镜的凹面反光镜反光，观察到的细胞数目更多，但细胞更小D. 在观察植物细胞有丝分裂实验中，先用低倍镜，再换用高倍镜On receiving a phone call from his wife ______ she had a fall, Mr. Gordon immediately rushed home from office. A．saysB．saidC．sayingD．tosay