单选题 Have you ever gone to a concert and realized that your seats were right next to the booming speakers? Are you guilty【C1】______turning up the volume on your portable cassette or CD player to drown out the whining of your little brother? Sometimes it's difficult to avoid loud music or noises, but they can be bad news because loud noises can【C2】______temporary or permanent hearing loss. Extremely loud music and noises that go on for long periods of time are common causes of deafness. If a noise is so loud that you have to shout to make yourself【C3】______. there is a【C4】______that the mechanism inside your ear can be injured. Temporary hearing loss can happen after you've been exposed to loud noise for only 15 minutes. If you have temporary hearing loss, you won't be able to hear as【C5】______as you normally can, and you may have tinnitus, which is a fancy word for ringing in the ears. Your ears call feel "full", too. 【C6】______, these things usually go away and your hearing soon return to normal. Permanent hearing loss can happen when someone is exposed to loud noise over and over. Construction workers and people who work in factories must【C7】______ear protectors because the equipment they use can be extremely loud. But even some lawn mowers and power tools can permanently【C8】______a person's ability to hear high-pitched noises and can also give him permanent tinnitus. Listening to extremely loud music over and over can also have the same effect on a person's hearing. And using headphones on a portable cassette or CD player can be dangerous【C9】______if the volume is too high and the headphones are used a lot, the noise can damage the ears. The best way to avoid hearing loss is to wear ear protectors when working with machinery and earplugs when going to a concert. Headphones are OK to wear when you're listening to music; just be sure the volume isn't too high, and give them a rest【C10】______once in a while.