The simple act of surrendering a telephone number to a store clerk may not seem harmful — so much so that many consumers do it with no questions asked . Yet that one action can set in motion a cascade of silent events , as that data point is acquired , analyzed , categorized , stored and sold over and over again . Future attacks on your privacy may come from anywhere , from anyone with money to purchase that phone number you surrendered . If you doubt the multiplier effect , consider your e - mail inbox . If it's loaded with spam , it's undoubtedly because at some point in time you unknowingly surrendered your e - mall to the wrong Web site . Do you think your telephone number or address is handled differently ? A cottage industry of small companies with names you've probably never heard of — like Acxiom or Merlin — buy and sell your personal information the way other commodities like corn or cattle futures are bartered . You may think your cell phone is unlisted , but if you've ever ordered a pizza , it might not be . Merlin is one of many commercial data brokers that advertises sale of unlisted phone numbers compiled from various sources — including pizza delivery companies . These unintended , unpredictable consequences that flow from simple actions make privacy issues difficult to grasp , and grapple with . In a larger sense , privacy also is often cast as a tale of " Big Brother "— the government is watching you or An big corporation is watching you . But privacy issues don't necessarily involve large faceless institutions : A spouse takes a casual glance at her husband's Blackberry , a co - worker looks at e - mall over your shoulder or a friend glances at a cell phone text message from the next seat on the bus . while very little of this is news to anyone — people are now well aware there are video cameras and Internet cookies everywhere — there is abundant evidence that people live their lives ignorant of the monitoring , assuming a mythical level of privacy . People write e - mails and type instant messages they never expect anyone to see . Just ask Mark Foley or even Bill Gates , whose e - mails were a cornerstone of the Justice Department's antitrust case against Microsoft . And polls and studies have repeatedly shown that Americans are indifferent to privacy concerns . The general defense for such indifference is summed up a single phrase : " I have nothing to hide ." If you have nothing to hide , why shouldn't the government be able to peek at your phone records , your wife see your e - mail or a company send you junk mail ? It's a powerful argument , one that privacy advocates spend considerable time discussing and strategizing over . It is hard to deny , however , that people behave different when they're being watched . And it is also impossible to deny that Americans are now being watched more than at any time in history . 1. In the first paragraph , the telephone number is cited to show A . many customers didn't keep their privacy confidential . B . it is harmful to give a store clerk a telephone number . C . careless disposal of personal information can be harmful . D . customers should inquire its use when giving telephone numbers to others . 2. What do companies like Acxiom and Merlin do ? A . Compile telephone directories for businessmen . B . Collect and sell personal information to make a profit . C . Trade commodities like corn on the market . D . Crack down crimes like stealing private information . 3. From Paragraph 3, we learn that A . cases of privacy intrusion happen only in large institutions . B . people are quite aware of how their privacy is intruded . C . it is not privacy intrusion when a wife glances at her husband's cell phone . D . Bill Gates' email messages were cited as evidence against him .。