根据材料,回答题: People buy cell phones for the following reasons EXCEPT that__________. A.they're popular. B.they're cheap. C.they're useful. D.they're convenient.
参考答案:
答案解析:
Eyespots,the most rudimentary eyes, are found in protozoan f
Eyespots,the most rudimentary eyes, are found in protozoan flagellates,flatworms