托福考试

根据网考网考试中心的统计分析，以下试题在2018/3/18日托福考试习题练习中，答错率较高，为：30%
【单选题】 According to paragraph 2, which of the following has made the study of pheromones difficult
A．Pheromones cannot be easily reproduced in chemical laboratories
B．Existing technology cannot fully explore the properties of pheromones
C．Pheromones are highly volatile
D．Pheromone signals are constantly changing

网考网参考答案：B，答错率：30%
网考网试题解析：
暂时没有解析查看试题解析出处>>