Hackers are classified as a human threat and not a classification by itself.
All the other answers are incorrect. Threats result from a variety of factors, although they are classified in three types: Natural (e.g., hurricane, tornado, flood and fire), human (e.g. operator error, sabotage, malicious code) or technological (e.g. equipment failure, software error, telecommunications network outage, electric power failure).
Reference: SWANSON, Marianne, & al., National Institute of Standards and Technology (NIST), http://csrc.nist.gov/publications/ nistpubs/800-34-rev1/sp800-34-rev1_errata-Nov11-2010.pdf, June 2002 (page 6).

With mirroring, the system writes the data simultaneously to separate drives or arrays.
The advantage of mirroring are minimal downtime, simple data recovery, and increased performance in reading from the disk.
The disadvantage of mirroring is that both drives or disk arrays are processing in the writing to disks function, which can hinder system performance.
Mirroring has a high fault tolerance and can be implemented either through a hardware RAID controller or through the operating system. Since it requires twice the disk space than actual data, mirroring is the less cost-efficient data redundancy strategy.
Source: SWANSON, Marianne, & al., National Institute of Standards and Technology (NIST), NIST Special Publication 800-34, Contingency Planning Guide for Information Technology Systems, December 2001 (page 45).

A vulnerability is a weakness in a system that can be exploited by a threat. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 237.

A sag is a momentary low voltage. A spike is a momentary high voltage. A fault is a momentary power out and a brownout is a prolonged power supply that is below normal voltage. Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, chapter 6: Physical security (page 299)

Scanning is definitively a very active attack. The attacker will make use of a scanner to perform the attack, the scanner will send a very large quantity of packets to the target in order to illicit responses that allows the attacker to find information about the operating system, vulnerabilities, misconfiguration and more. The packets being sent are sometimes attempting to identify if a known vulnerability exist on the remote hosts.
A passive attack is usually done in the footprinting phase of an attack. While doing your passive reconnaissance you never send a single packet to the destination target. You gather information from public databases such as the DNS servers, public information through search engines, financial information from finance web sites, and technical infomation from mailing list archive or job posting for example.
An attack can be active or passive. An “active attack” attempts to alter system resources or affect their operation.
A “passive attack” attempts to learn or make use of information from the system but does not affect system resources. (E.g., see: wiretapping.)
The following are all incorrect answers because they are all passive attacks:
Traffic Analysis -Is the process of intercepting and examining messages in order to deduce information from patterns in communication. It can be performed even when the messages are encrypted and cannot be decrypted. In general, the greater the number of messages observed, or even intercepted and stored, the more can be inferred from the traffic. Traffic analysis can be performed in the context of military intelligence or counter-intelligence, and is a concern in computer security.
Eavesdropping -Eavesdropping is another security risk posed to networks. Because of the way some networks are built, anything that gets sent out is broadcast to everyone. Under normal circumstances, only the computer that the data was meant for will process that information. However, hackers can set up programs on their computers called “sniffers” that capture all data being broadcast over the network. By carefully examining the data, hackers can often reconstruct real data that was never meant for them. Some of the most damaging things that get sniffed include passwords and credit card information.
In the cryptographic context, Eavesdropping and sniffing data as it passes over a network are considered passive attacks because the attacker is not affecting the protocol, algorithm, key, message, or any parts of the encryption system. Passive attacks are hard to detect, so in most cases methods are put in place to try to prevent them rather than to detect and stop them. Altering messages, modifying system files, and masquerading as another individual are acts that are considered active attacks because the attacker is actually doing something instead of sitting back and gathering data. Passive attacks are usually used to gain information prior to carrying out an active attack.”
Wiretapping -Wiretapping refers to listening in on electronic communications on telephones, computers, and other devices. Many governments use it as a law enforcement tool, and it is also used in fields like corporate espionage to gain access to privileged information. Depending on where in the world one is, wiretapping may be tightly controlled with laws that are designed to protect privacy rights, or it may be a widely accepted practice with little or no protections for citizens. Several advocacy organizations have been established to help civilians understand these laws in their areas, and to fight illegal wiretapping.
Reference(s) used for this question:
HARRIS, Shon, All-In-One CISSP Certification Exam Guide, 6th Edition, Cryptography, Page 865 and http://en.wikipedia.org/wiki/Attack_%28computing%29 and http://www.wisegeek.com/what-is-wiretapping.htm and https://pangea.stanford.edu/computing/resources/network/security/ri… and http://en.wikipedia.org/wiki/Traffic_analysis

The Business Impact Analysis is critical for the development of a business continuity plan (BCP). It identifies risks, critical processes and resources needed in case of recovery and quantifies the impact a disaster will have upon the organization. The development of a mission statement is normally performed before the BIA.
A BIA (business impact analysis ) is considered a functional analysis, in which a team collects data through interviews and documentary sources; documents business functions, activities, and transactions ; develops a hierarchy of business functions; and finally applies a classification scheme to indicate each individual function’s criticality level.
BIA Steps The more detailed and granular steps of a BIA are outlined here:
1. Select individuals to interview for data gathering.
2. Create data-gathering techniques (surveys, questionnaires, qualitative and quantitative approaches).
3. Identify the company’s critical business functions.
4. Identify the resources these functions depend upon.
5. Calculate how long these functions can survive without these resources.
6. Identify vulnerabilities and threats to these functions.
7. Calculate the risk for each different business function.
8. Document findings and report them to management.
Reference(s) used for this question: Hernandez CISSP, Steven (2012-12-21). Official (ISC)2 Guide to the CISSP CBK, Third Edition ((ISC)2 Press) (Kindle Location 21076). Auerbach Publications. Kindle Edition. and Harris, Shon (2012-10-18). CISSP All-in-One Exam Guide, 6th Edition (p. 905-910). McGraw-Hill. Kindle Edition.

The full backup makes a complete backup of every file on the system every time it is run. Since a single backup set is needed to perform a full restore, it is appropriate for off-site archiving. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 69).

The incremental backup method only copies files that have been recently changed or added. Only files with their archive bit set are backed up. This method is fast and uses less tape space but has some inherent vulnerabilities, one being that all incremental backups need to be available and restored from the date of the last full backup to the desired date should a restore be needed. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 69).

The differential backup method only copies files that have changed since the last full backup was performed. It is additive in the fact that it does not reset the archive bit so all changed or added files are backed up in every differential backup until the next full backup. The “additive backup method” is not a common backup method. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 69).

A differential backup is a partial backup that copies a selected file to tape only if the archive bit for that file is turned on, indicating that it has changed since the last full backup. A differential backup leaves the archive bits unchanged on the files it copies.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 69).
Also see: http://e-articles.info/e/a/title/Backup-Types/
Backup software can use or ignore the archive bit in determining which files to back up, and can either turn the archive bit off or leave it unchanged when the backup is complete. How the archive bit is used and manipulated determines what type of backup is done, as follows
Full backup
A full backup, which Microsoft calls a normal backup, backs up every selected file, regardless of the status of the archive bit. When the backup completes, the backup software turns off the archive bit for every file that was backed up. Note that “full” is a misnomer because a full backup backs up only the files you have selected, which may be as little as one directory or even a single file, so in that sense Microsoft’s terminology is actually more accurate. Given the choice, full backup is the method to use because all files are on one tape, which makes it much easier to retrieve files from tape when necessary. Relative to partial backups, full backups also increase redundancy because all files are on all tapes. That means that if one tape fails, you may still be able to retrieve a given file from another tape. Differential backup
A differential backup is a partial backup that copies a selected file to tape only if the archive bit for that file is turned on, indicating that it has changed since the last full backup. A differential backup leaves the archive bits unchanged on the files it copies. Accordingly, any differential backup set contains all files that have changed since the last full backup. A differential backup set run soon after a full backup will contain relatively few files. One run soon before the next full backup is due will contain many files, including those contained on all previous differential backup sets since the last full backup. When you use differential backup, a complete backup set comprises only two tapes or tape sets: the tape that contains the last full backup and the tape that contains the most recent differential backup. Incremental backup
An incremental backup is another form of partial backup. Like differential backups, Incremental Backups copy a selected file to tape only if the archive bit for that file is turned on. Unlike the differential backup, however, the incremental backup clears the archive bits for the files it backs up. An incremental backup set therefore contains only files that have changed since the last full backup or the last incremental backup. If you run an incremental backup daily, files changed on Monday are on the Monday tape, files changed on Tuesday are on the Tuesday tape, and so forth. When you use an incremental backup scheme, a complete backup set comprises the tape that contains the last full backup and all of the tapes that contain every incremental backup done since the last normal backup. The only advantages of incremental backups are that they minimize backup time and keep multiple versions of files that change frequently. The disadvantages are that backed-up files are scattered across multiple tapes, making it difficult to locate any particular file you need to restore, and that there is no redundancy. That is, each file is stored only on one tape.
Full copy backup
A full copy backup (which Microsoft calls a copy backup) is identical to a full backup except for the last step. The full backup finishes by turning off the archive bit on all files that have been backed up. The full copy backup instead leaves the archive bits unchanged. The full copy backup is useful only if you are using a combination of full backups and incremental or differential partial backups. The full copy backup allows you to make a duplicate “full” backup—e.g., for storage offsite, without altering the state of the hard drive you are backing up, which would destroy the integrity of the partial backup rotation. Some Microsoft backup software provides a bizarre backup method Microsoft calls a daily copy backup. This method ignores the archive bit entirely and instead depends on the date-and timestamp of files to determine which files should be backed up. The problem is, it’s quite possible for software to change a file without changing the date-and timestamp, or to change the date-and timestamp without changing the contents of the file. For this reason, we regard the daily copy backup as entirely unreliable and recommend you avoid using it.