阅读理解。 'Millions of young people will lose their hearing in five years if they listen to MP3 or MP4 players at a too high voice every day,' scien tists say recently. Do you often listen to MP3 players at a too high voice? Are you frightened to hear this? The sizes of MP3 players are very small, but small MP3 players make it easy to take hundreds of songs with you. So many young people carry them and listen to music every day. MP3 players are very popular among students. The scientists say teenagers should be far from high volume (音量), including mobile phones' nois e. A study says, 'High volume and long listening time can cause hearing problems.' They think if young people listen at more than 89 decibels (分贝) every day, they will lose their hearing in five years. A scientist said, 'So many young people often use personal music players and mobile phones at a high voice. I am afraid that they may be losing their hearing. So let's turn our MP3 players down! 1. According to the passage, which of the following is true? A. Scientists tell young people to turn off their MP3 players. B. Teenagers will lose their hearing if they listen to hundreds of songs in MP3 players. C. A person will lose hearing in 5 years if he or she listens to an MP3 player every day. D. The mobile phone can also cause hearing problems if we don't use it correctly. 2. The underlined word ' they ' (Paragraph 4) most probably refers to ______. A. scientists B. MP3 players C. mobile phones D. teenagers 3. Which might be the best title for this passage? A. Turn your MP3 players down! B. Never us e MP3! C. How to protect your hearing. D. Young people's hearing.