Kerberos is a trusted, credential-based, third-party authentication protocol
that uses symmetric (secret) key cryptography to provide robust authentication to clients
accessing services on a network.
One weakness of Kerberos is its Key Distribution Center (KDC), which represents a single
point of failure.
The KDC contains a database that holds a copy of all of the symmetric/secret keys for the
principals.
Reference(s) used for this question:
KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten
Domains of Computer Security, John Wiley & Sons, 2001, Chapter 2: Access control
systems (page40).

Section: Access Control
Explanation/Reference:
In order to protect the confidentiality of the data.
The following answers are incorrect because :
Install a firewall is incorrect as this would come after the information has been identified for sensitivity levels.
Implement encryption is also incorrect as this is one of the mechanisms to protect the data once it has been identified.
Review all user access rights is also incorrect as this is also a protection mechanism for the identified information.
Reference : Shon Harris AIO v3 , Chapter-4 : Access Control , Page : 126

As session key is a symmetric key that is used to encrypt messages between
two users. A session key is only good for one communication session between users.
For example , If Tanya has a symmetric key that she uses to encrypt messages between
Lance and herself all the time , then this symmetric key would not be regenerated or
changed. They would use the same key every time they communicated using encryption.
However , using the same key repeatedly increases the chances of the key being captured
and the secure communication being compromised. If , on the other hand , a new
symmetric key were generated each time Lance and Tanya wanted to communicate , it
would be used only during their dialog and then destroyed. if they wanted to communicate
and hour later , a new session key would be created and shared.
The other answers are not correct because :
Public Key can be known to anyone.
Private Key must be known and used only by the owner.
Secret Keys are also called as Symmetric Keys, because this type of encryption relies on
each user to keep the key a secret and properly protected.
REFERENCES:
SHON HARRIS , ALL IN ONE THIRD EDITION : Chapter 8 : Cryptography , Page : 619-

Explanation/Reference:
A memory dump can be admitted as evidence if it acts merely as a statement of fact. A system dump is not considered hearsay because it is used to identify the state of the system, not the truth of the contents. The exclusionary rule mentions that evidence must be gathered legally or it can't be used. This choice is a distracter.
Source: ANDRESS, Mandy, Exam Cram CISSP, Coriolis, 2001, Chapter 10: Law, Investigation, and Ethics (page 187).

Explanation/Reference:
Security testing and trusted distribution are required for Life-Cycle Assurance.
The following answers are incorrect:
System Architecture and Design specification. Is incorrect because System Architecture is not requried for Life-Cycle Assurance.
Security Testing and Covert Channel Analysis. Is incorrect because Covert Channel Analysis is not requried for Life-Cycle Assurance.
Configuration Management and Trusted Facility Management. Is incorrect because Trusted Facility Management. is not requried for Life-Cycle Assurance.