Data diddling is an active attack opposed to a passive attack. Reference: "Data Diddling occurs when an attacker gains access to a system and makes small, random, or incremental changes to data rather than obviously altering file contents or damaging or deleting entire files." Pg 383 Tittel

Most backup methods use the Archive file attribute to determine whether the file should be backed up or not. The backup software determines which files need to be backed up by checking to see if the Archive file attribute has been set, and then resets the Archive bit value to null after the backup procedure. The Incremental Backup Method backs up only files that have been created or modified since the last backup was made, because the Archive file attribute is reset. This can result in the backup operator needing several tapes to do a complete restoration, as every tape with changed files as well as the last full backup tape will need to be restored.
*a Full or Complete backup backs up all files in all directories stored on the server regardless of when the last backup was made and whether the files have already been backed up. The Archive file attribute is changed to mark that the files have been backed up, and the tapes or tapes will have all data and applications on it. It's an incorrect answer for this question, however, as it's assumed answers Differential Backup Method and Incremental Backup Method will additionally require differential or incremental tapes.
*the Differential Backup Method, backs up only files that have been created or modified since the last backup was made, like an incremental backup. However, the difference between an incremental backup and a differential backup is that the Archive file attribute is not reset after the differential backup is completed, therefore the changed file is backed up every time the differential backup is run. The backup set grows in size until the next full backup as these files continue to be backed up during each subsequent differential backup, until the next complete backup occurs. The advantage of this backup method is that the backup operator should only need the full backup and the one differential backup to restore the system. Table shows these three backup methods.
Exhibit:

Answer "Ad Hoc Backup Method" is a distracter.

The correct answer is "Procedures are step-by-step instructions for compliance with mandatory standards". The other answers are incorrect.

Statistical multiplexing is a type of communication link sharing, very similar to dynamic bandwidth allocation (DBA). In statistical multiplexing, a communication channel is divided into an arbitrary number of variable bit-rate digital channels or data streams. The link sharing is adapted to the instantaneous traffic demands of the data streams that are transferred over each channel. This is an alternative to creating a fixed sharing of a link, such as in general time division multiplexing (TDM) and frequency division multiplexing
(FDM). When performed correctly, statistical multiplexing can provide a link utilization improvement, called the statistical multiplexing gain.
Generally, the methods for multiplexing data include the following :
Time-division multiplexing (TDM): information from each data channel is allocated bandwidth based on pre-assigned time slots, regardless of whether there is data to transmit. Time-division multiplexing is used primarily for digital signals, but may be applied in analog multiplexing in which two or more signals or bit streams are transferred appearing simultaneously as sub-channels in one communication channel, but are physically taking turns on the channel. The time domain is divided into several recurrent time slots of fixed length, one for each sub-channel. A sample byte or data block of sub-channel 1 is transmitted during time slot 1, sub-channel 2 during time slot 2, etc. One TDM frame consists of one time slot per sub-channel plus a synchronization channel and sometimes error correction channel before the synchronization. After the last sub-channel, error correction, and synchronization, the cycle starts all over again with a new frame, starting with the second sample, byte or data block from sub-channel 1, etc.
Asynchronous time-division multiplexing (ATDM): information from data channels is allocated bandwidth as needed, via dynamically assigned time slots. ATM provides functionality that is similar to both circuit switching and packet switching networks: ATM uses asynchronous time-division multiplexing, and encodes data into small, fixed-sized packets (ISO-OSI frames) called cells. This differs from approaches such as the Internet
Protocol or Ethernet that use variable sized packets and frames. ATM uses a connection- oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins. These virtual circuits may be "permanent", i.e. dedicated connections that are usually preconfigured by the service provider, or "switched", i.e. set up on a per-call basis using signalling and disconnected when the call is terminated.
Frequency division multiplexing (FDM): information from each data channel is allocated bandwidth based on the signal frequency of the traffic. In telecommunications, frequency- division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping frequency sub-bands, each of which is used to carry a separate signal. This allows a single transmission medium such as the radio spectrum, a cable or optical fiber to be shared by many signals.
Reference used for this question:
http://en.wikipedia.org/wiki/Statistical_multiplexing
and
http://en.wikipedia.org/wiki/Frequency_division_multiplexing
and
Information Systems Audit and Control Association, Certified Information Systems Auditor
2 002 review manual, Chapter 3: Technical Infrastructure and Operational Practices (page
1 14).