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2.You maintain daily backups of a large file, as well as calculating an MD5 checksum with md5sum. When verifying the contents of one such backup, you notice that the new checksum is different from the previous one by only one byte. What does this tell you about the contents of the file?

A single character in the original file has been modified.
1/32nd of the original file has been modified.
1/128th of the original file has been modified.
It tells you that the original file has been modified.
The contents of the file are in reverse order from the original.

Explanation: The MD5 (Message Digest number 5) value for a file is a 128-bit value similar to a checksum. This value is calculated according to the contents of a file. If a file has changed, the MD5/checksum value will be different.

Reference: http://www.iay.pwp.blueyonder.co.uk/threel/tech/tools/md5.htm

Incorrect Answers
A: A different checksum means that the file has changed. However, it offers no indication of how much of the file has changed.
B: A different checksum means that the file has changed. However, it offers no indication of how much of the file has changed.
C: A different checksum means that the file has changed. However, it offers no indication of how much of the file has changed.
E: A different checksum means that the file has changed. However, it offers no indication of how much of the file has changed.
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