It is a data integrity assurance software aimed at detecting and reporting accidental
or malicious changes to data.
The following answers are incorrect :
Nessus is incorrect as it is a vulnerability scanner used by hackers in discovering vulnerabilities in
a system.
Saint is also incorrect as it is also a network vulnerability scanner likely to be used by hackers.
Nmap is also incorrect as it is a port scanner for network exploration and likely to be used by
hackers.
Reference :
Tripwire : http://www.tripwire.com
Nessus : http://www.nessus.org
Saint : http://www.saintcorporation.com/saint
Nmap : http://insecure.org/nmap

ALE = ARO x SLE = 0.2 x 70,000 = 14,000

Explanation/Reference:
Explanation:
Digital Audio Tape (DAT) can be used to backup data systems in addition to its original intended audio uses.
Incorrect Answers:
A: Digital Video Tape (DVT) is not used to backup data systems.
B: Digital Analog Tape (DAT) is not a defined type of tape; DAT stands for Digital Audio Tape.
C: Digital Voice Tape (DVT) is not a defined type of tape; DVT stands for Digital Video Tape.
References:
Krutz, Ronald L. and Russel Dean Vines, The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, New York, 2001, p. 70

Copying sector by sector at the bit level provides the capability to examine slack space, undeleted clusters and possibly, deleted files.
With answer a, only the system files are copied and the other information recovered in answer b would not be captured.
Answer "Copying the disk directory" does not capture the data on the disk, and answer "Copying and authenticating the system files " has the same problem as answer "Copying the system files". Actually, authenticating the system files is another step in the computer forensics process wherein a message digest is generated for all system directories and files to be able to validate the integrity of the information at a later time. This authentication should be conducted using a backup copy of the disk and not the original to avoid modifying information on the original. For review purposes, computer forensics is the collecting of information from and about computer systems that is admissible in a court of law.