选项A说科学实验表明手机的使用不会伤害人们的健康，这与录音内容所 说的表面意思很相近，即 there is little evidence that cellphone signals raise the risk of brain cancer (科学的主流意见一致认为很少有证据证明手机信号有增加脑肿瘤的风 险），但是在细节上，考题选项说的是没有具体限定的肯定的论断，而后者只是说 很少有证据能证明手机信号损伤大脑（有增加脑肿瘤的风险），但没有提及其他可 能的伤害。所以选项A 可以排除。选项B 虽然从理性上是正确的，但只是一般的推断，并非问题所问的main point of this passage。选项C 也可以直接排除，因为它 与录音一开始就可以听到的第一句话意思互相矛盾，关于手机信号的问题既然有 scientific consensus，那么再说 Scientists’ opinions are split...就不能成立。这样一来 选项D 就成了唯一正确选择。

[重点难点]
根据关键词区分话语意义的细微差异。

[录音原文]
Mainstream scientific consensus holds that there is little evidence that cellphone signals raise the risk of brain cancer; rather, behaviors like texting while driving are seen as the real health concerns. Nevertheless, more than 500 pages of internal records obtained by The New York Times, along with interviews with former agency officials, reveal a debate and some disagreement among scientists and health agencies about what guidance to give as the use of mobile devices skyrockets.