Explanation/Reference:
Explanation:
Symmetric cryptography is much faster than asymmetric systems, and is difficult to crack if a large key size is used.
Incorrect Answers:
A, B, D: Symmetric cryptography provides confidentiality, but not authenticity or nonrepudiation, and therefore deemed limited. It requires a secure mechanism to deliver keys correctly. Each pair of users needs a unique key. Therefore, as the number of individuals increase, so does the number of keys.
These are all considered weaknesses of symmetric cryptography.
References:
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, p. 783

The best location for a new data center within a multifloor building is in the core of the building. This location can minimize the emanations and enhance the physical access controls. Emanations are the electromagnetic signals or radiation that are emitted by electronic devices, such as computers, servers, or network equipment.
Emanations can be intercepted or captured by attackers to obtain sensitive or confidential information.
Physical access controls are the measures that prevent or restrict unauthorized or malicious access to physical assets, such as data centers, servers, or network devices. Physical access controls can include locks, doors, gates, fences, guards, cameras, alarms, etc. The core of the building is the central part of the building that is usually surrounded by other rooms or walls. This location can reduce the emanations by creating a shielding effect and increasing the distance from the potential attackers. The core of the building can also improve the physical access controls by limiting the entry points and visibility of the data center12 References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 3: Security Engineering, p. 133; Official (ISC)2 CISSP CBK Reference, Fifth Edition, Domain 3: Security Engineering, p. 295.

The correct answer is Trusted system, by definition of a trusted system.
Answers Closed system and Open system refer to open, standard information on a product as opposed to a closed or proprietary product. Answer Safe system is a distracter.

The correct answer is "Configuration review", a distracter.
*Answer configuration control involves controlling changes to configuration items and
issuingversions of configuration items from the software library.
*Configuration status accountingis the processing of changes.
* Configuration audit is the process of controlling the quality of configuration management procedures.

The dynamic packet filtering firewall is able to create ACL's on the fly to allow replies on dynamic ports (higher than 1023).
Packet filtering is incorrect. The packet filtering firewall usually requires that the dynamic ports be left open as a group in order to handle this situiation.
Circuit level proxy is incorrect. The circuit level proxy builds a conduit between the trusted and untrusted hosts and does not work by dynamically creating ACL's.
Application level proxy is incorrect. The application level proxy "proxies" for the trusted host in its communications with the untrusted host. It does not dynamically create ACL's to control traffic.