The convenience and efficiency of electronic mail are threatened by the extremely rapid growth in the volume of unsolicited commercial electronic mail. Unsolicited commercial electronic mail is currently estimated to account for over half of all electronic mall traffic, up from an estimated 7 percent in 2001, and the volume continues to rise. Most of these messages are fraudulent or deceptive in one or more respects.

　　The receipt of unsolicited commercial electronic mail may result in costs to recipients who cannot refuse to accept such mail and who incur costs for the storage of such mail, or for the time spent accessing, reviewing, and discarding such mail, or for both. The receipt of a large number of unwanted messages also decreases the convenience of electronic mall and creates a risk that wanted electronic mail messages, both commercial and noncommercial, will be lost, overlooked, or discarded amidst the larger volume of unwanted messages, thus reducing the reliability and usefulness of electronic mail to the recipient. Some commercial electronic mail contains material that many recipients may consider vulgar or pornographic in nature.

　　The growth in unsolicited commercial electronic mail imposes significant monetary costs on providers of Internet access services, businesses, and educational and nonprofit institutions that carry and receive such mail, as there is a finite volume of mail that such providers, businesses, and institutions can handle without further investment in infrastructure. Many senders of unsolicited commercial electronic mail purposefully disguise the source of such mall.

　　Many senders of unsolicited commercial electronic mall purposefully include misleading information in the messages' subject lines in order to induce the recipients to view the messages. While some senders of commercial electronic mail messages provide simple and reliable ways for recipients to reject (or 'opt-out' of) receipt of commercial electronic mall from such senders in the future, other senders provide no such 'opt-out' mechanism, or refuse to honor the requests of recipients not to receive electronic mail from such senders in the future, or both.

　　Many senders of bulk unsolicited commercial electronic mail use computer programs to gather large numbers of electronic mail addresses on an automated basis from Internet websites or online services where users must post their addresses in order to make full use of the website or service.

　　The problems associated with the rapid growth and abuse of unsolicited commercial electronic mall cannot be solved by the government alone. The development and adoption of techno-logical approaches and the pursuit of cooperative efforts with other countries will be necessary as well.

　　91. According to the passage, efficiency of e-mail is threatened by ______mcjgcyingcheng.com

　　A. heavy e-mail traffic

　　B. fraudulent e-mail messages

　　C. large volume of messages

　　D. increasing amount of unwanted e-mail

　　92. Which of the following is NOT true about unwanted e-mail?

　　A. It costs money to receive them.

　　B. It's free to store them.

　　C. It takes time to access them.

　　D. It takes time to throw them away.

　　93. Unwanted e-mail may ______

　　A. cause companies to fail in business

　　B. cause wanted e-mail messages to lose

　　C. damage the credit of a company

　　D. do good to a small company

　　94. "Pornographic" in Paragraph 3 probably means ______

　　A. decent B. instructional

　　C. sexual D. commercial

　　95. What does unwanted e-mail messages do to the providers of the Internet services?

　　A. Raising their cost.

　　B. Raising the Internet speed.

　　C. Improving their business.

　　D. Attracting investment.

　　96. "Disguise" in Paragraph 4 is closest in meaning to ______

　　A. reveal B. hide

　　C. deliver D. post

　　97. The word "induce" in Paragraph 5 is closest in meaning to ______

　　A. cheat B. introduce

　　C. provide D. harm

　　98. "Opt-out" mechanism is probably ______

　　A. a machine that can be attached to your computer

　　B. a button that you can make a choice to read or not to read

　　C. a software that you can play a computer game

　　D. an e-mail that says some good words to you

　　99. It can be inferred from Paragraph 6 that bulk unsolicited commercial e-mail will probably spread ______

　　A. harmful virus B. unpleasant news

　　C. advertisements D. adult jokes

　　100. The unwanted e-mail problem can be solved if ______

　　A. the government takes action

　　B. a new technology is adopted

　　C. more people are aware of the problem

　　D. joint efforts are made and new technology is used