tailieunhanh - Cracking the toefl ibt 2008 part 17

Each digital organism consists of a pattern o1 code. TTie organisms compete with one another for resources, and the most successful ones are able to make more copies of themselves. Just like a living creature, the digital entities also undergo mutations. Mutations that are beneficial ensure greater reproduction; harmful mutations have the opposite effect. | 1. The word most nearly means A growth B spread C advancement D enlargement 2. In the first paragraph the author describes spam as A a recent problem that affects millions of users B totaling more than 80 percent of E-mails sent via the Internet C a technological innovation D unwanted messages sent to a mass audience 3. In the passage the word is closest in meaning to A unknowingly B disastrously C disappointingly D extremely 4. The phrase the prdgrairt refers to A spam messages B random characters and numbers Q a type of spam filter D common features 5 According to paragraph 4 smart filters are superior to fingerprinting systems because smart filters A are eventually able to recognize new versions of spam messages B are able to learn from their mistakes C do not need to find common features to detect spam D are not fooled by random characters or content READING PRACTICE DRILLS 173 6. Which of the choices below best expresses the meaning of the highlighted sentence in the passage Incorrect answer choices change the meaning in important ways or leave out essential information. A Once spammers figured out how smart filters functioned they were able to defeat them by changing words in the message. B Spammers can avoid smart filters by replacing certain letters in words or phrases with other characters. C Smart filters function by looking for words that have certain letters replaced by numbers. D A smart filter is easily defeated by spammers who are able to disguise words and phrases with numbers and characters. 7 The word automated as used in the passage most nearly means A computerized B automatic C costly D illegal 8 The passage mentions all of the following as hindrances to adopting verification systems EXCEPT A user reluctance B inconvenience C ineffectiveness D violation of privacy 9. The author describes the fight over spam as an arms race because A computer engineers and spammers are constantly reacting to each other s strategies B some of the techniques used .