题目

Ⅲ  阅读（共两节。满分40分） 阅读理解（共15小题；每小题2分，满分30分） 阅读下列短文，从每题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。                               The evidence for harmony may not be obvious in some families. But it seems that four out of five young people now get on with their parents, which is the opposite of the popularly-held image （形象）of unhappy teenagers locked in their room after endless family quarrels. An important new study into teenage attitude关于声音的说法正确的是（ ）A. 物体只要振动，人们就能听到声音 B. 声音只能通过介质传播C. 声音在一切介质中的传播速度都是相同的 D. 声音中，人们听不见的声音只有超声波