【答案解析】解析：情景事实题。短文开篇讲到“And the first actual radio broadcast was made on Christmas Eve of 1906．”，即真正能用来广播的装置是De Forest于1906年圣诞夜时做成的。故选项A为正确答案。
【正确答案】
C
【答案解析】解析：情景事实题。根据录音“The following year，De Forest began regular radio broadcasts in New York．”可知，选项C为正确答案。选项D具有较强的干扰性，但要注意纽约码头的船上是接收广播的地点，而不是De Forest播放广播的地点。
【正确答案】
B
【答案解析】解析：语义理解题。根据录音“For the simple fact that only a few people，in fact，only those who tinkered with wireless telegraphs as a hobby，owned receivers．”可知，只有那些喜爱无线电的人才有接收机。因此选项B为正确答案。
【正确答案】
D
【答案解析】解析：语义理解题。根据录音“This was radio pioneer，David Sarnoff，who predicted that one day there would be a radio receiver in every home．”可知，总有一天，每个家庭都将拥有无线电收音机。故选项D为正确答案。