Identification and authentication is a technical measure that prevents unauthorized people (or unauthorized processes) from entering an IT system. Access control usually requires that the system be able to identify and differentiate among users. Reporting incidents is more related to incident response capability (operational control) than to identification and authentication
(technical control).
Source: SWANSON, Marianne, NIST Special Publication 800-26, Security Self-Assessment Guide
for Information Technology Systems, November 2001 (Pages A-30 to A-32).

The Orange book requires protection against two types of covert channels,
Timing and Storage.
The following answers are incorrect:
Storage and low bits. Is incorrect because, low bits would not be considered a covert channel.
Storage and permissions. Is incorrect because, permissions would not be considered a covert channel.
Storage and classification. Is incorrect because, classification would not be considered a covert channel.

Reference: "Emergency system restart is done after a system fails in an uncontrolled manner in response to a TCB or media failure. In such cases, TCB and user objects on nonvolatile storage belonging to processes active at the time of TCB or media failure may be left in an inconsistent state. The system enters maintenance mode, recovery is performed automatically, and the system restarts with no user processes in progress after bringing up the system in a consistent state."

The CAis used in public key cryptography, not secret key cryptography.
A CA will certify that a public key actually belongs to a specific
individual and that the information associated with the
individual's key is valid and correct. The CA accomplishes this certification by digitally signing the individual's public key and associated information. The certification professes to another person who
wants to send a message to this individual using public key encryption
that the public key actually belongs to the intended individual.
The Consultation Committee, International Telephone and Telegraph,
International Telecommunications Union (CCITT-ITU)/
International Organization for Standardization (ISO) X.509 Authentication framework defines a format for public key certificates. This structure is outlined in Figure.

image012
Answer "A networked group of m users with separate keys for each pair of users will require m (m-1)/2 keys" is an important issue in secret key cryptography; therefore it is not the correct answer. If, among a network of m users, each user wants to have secure communications with every other user on the network, then there must be a secret key for each pair of potential users.
This concept can be illustrated with five users as shown in Figure.

image014
Thus, with five users, the number of independent keys is equal to (5 x
4)/2 or 10 as depicted by the ten connecting lines in Figure A.6.
*answer "Secure distribution of the keys" is incorrect since securely distributing the keys to all users is, obviously, a very important requirement.
Answer d is incorrect since a compromise of the keys can, indeed,
enable the attacker to impersonate the key owners and, therefore,
read and send false messages.

It must be noted that Halon is now banned in most countries or cities.
The reason CO2 is preferred in an information center is the agent is considered a clean agent, as
well as non-conductive. The agent evaporates and does not leave a residue on the equipment.
CO2 can be hazardous to people so special care must be taken when implemented.
Water may be a sound solution for large physical areas such as warehouses, but it is entirely
inappropriate for computer equipment. A water spray can irreparably damage hardware more
quickly than encroaching smoke or heat. Gas suppression systems operate to starve the fire of
oxygen. In the past, Halon was the choice for gas suppression systems; however, Halon leaves
residue, depletes the ozone layer, and can injure nearby personnel.
NOTE FROM CLEMENT:
For the purpose of the exam do not go outside of the 4 choices presented. YES, it is true that
there are many other choices that would be more adequate for a Data Centre. An agent such as
IG-55 from Ardent would probably be a better choice than CO2, however it is NOT in the list of
choices.
You will also notice that Shon Harris and Krutz and Vines disagree on which one is the best. This
is why you must do your own research to supplement the books, sometimes books could be
opiniated as well. When in doubt refer to the official book and look at what is ISC2 view of the topic
and which one ISC2 considers to be the best for the exam.
ISC2 recommends also the following:
Aero-K - uses an aerosol of microscopic potassium compounds in a carrier gas released from
small canisters mounted on walls near the ceiling. The Aero-K generators are not pressurized until
fire is detected. The Aero-K system uses multiple fire detectors and will not release until a fire is
"confirmed" by two or more detectors (limiting accidental discharge). The gas is non-corrosive, so
it does not damage metals or other materials. It does not harm electronic devices or media such
as tape or discs. More important, Aero-K is nontoxic and does not injure personnel.
FM-200 - is a colorless, liquefied compressed gas. It is stored as a liquid and dispensed into the
hazard as a colorless, electrically non-conductive vapor that is clear and does not obscure vision.
It leaves no residue and has acceptable toxicity for use in occupied spaces at design
concentration. FM-200 does not displace oxygen and, therefore, is safe for use in occupied
spaces without fear of oxygen deprivation.
The following are incorrect choices:
Water or Soda/Acid & Halon: (old water extinguishers) will damage sensitive equipment as well as
conduct electricity which could endanger the life of the person using such a fire extinghisher.
Halon has been banned due to the Montreal Protocol.
ABC rated Dry chemical extinguishers: They are suitable for electrically energized fires, but they are not acceptable on sensitive equipment. It is like throwing a couple kilograms of flour in around in a room. It is extremely hard to clean off of equipment and some of the chemicals are corrosive in nature.
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 Locations 25609-25612). Auerbach Publications. Kindle Edition. and http://www.ehs.ucf.edu/labsafe/safemgequip.html or http://www.osha.gov/doc/outreachtraining/htmlfiles/extmark.html