A:Why was it that
B:Why was that
C:Why was that it
D:Why was it
社会主义精神文明建设的根本任务是提高全民族的思想道德素质和科学文化素质。( )
“害人之心不可有,防人之心不可无”,为了防范侵害,我们必须提高警惕。( )
如图为某同学在观察洋葱鳞片叶外表皮细胞临时装片过程中,在显微镜下看到的几个视野,请据图回答: