单选题
Scientists do not know ________.
A、
how children learn their own languages
B、
when children begin to learn their own languages
C、
why children learn their own languages
【正确答案】
A
【答案解析】
[解析] 本题属于推断题。根据文章最后四句话可以推断，A所表述的是正确的。故本题答案为A。
提交答案
关闭