A certain computer program creates temporary files on the computer on which it is installed. The files contain a programming error, or "bug", that, in rare cases, may cause the computer to freeze up. The temporary files are purged 90 days after the program is installed. Since no program will copy the bug to any other file, any computer containing the program that freezes more than 90 days after the program has been installed does not freeze because of this program.
Which of the following,
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Which of the following,
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