A-A+
A．The high temperatures required for its use.B
问题详情
A．The high temperatures required for its use.
B．The lack of trained environmental engineers.
C．The opposition of automobile manufacturers.
D．The high cost of materials used in its production.
参考答案
正确答案：A
解析：听力材料最后女士的回答中提到了这种材料的缺陷：it's not really that easy及you first have to heat it over 10，000 degrees，即coniine oxide的使用需要高温，选项A是对女士回答的同义转述。
