Explanation/Reference:
It is usually responsible for maintaining and protecting the data.
The following answers are incorrect:
Data owner is usually a member of management , in charge of a specific business unit and is ultimately responsible for the protection and use of the information.
User is any individual who routinely uses the data for work-related tasks.
Security administrator's tasks include creating new system user accounts , implementing new security software.
References : Shon Harris AIO v3 , Chapter - 3: Security Management Practices , Pages : 99 - 103

Explanation/Reference:
The Data/Information Owner is ultimately responsible for the protection of the data. It is the Data/ Information Owner that decides upon the classifications of that data they are responsible for.
The data owner decides upon the classification of the data he is responsible for and alters that classification if the business need arises.
The following answers are incorrect:
Security Administrator. Is incorrect because this individual is responsible for ensuring that the access right granted are correct and support the polices and directives that the Data/Information Owner defines.
User. Is Incorrect because the user uses/access the data according to how the Data/Information Owner defined their access.
Auditor. Is incorrect because the Auditor is responsible for ensuring that the access levels are appropriate.
The Auditor would verify that the Owner classified the data properly.
References:
CISSP All In One Third Edition, Shon Harris, Page 121

The question mentions clearly "operating together". Which means the BEST answer is Dual Control.
Two mechanisms necessary to implement high integrity environments where separation of duties is paramount are dual control or split knowledge.
Dual control enforces the concept of keeping a duo responsible for an activity. It requires more than one employee available to perform a task. It utilizes two or more separate entities (usually persons), operating together, to protect sensitive functions or information.
Whenever the dual control feature is limited to something you know., it is often called split knowledge (such as part of the password, cryptographic keys etc.) Split knowledge is the unique "what each must bring" and joined together when implementing dual control.
To illustrate, let say you have a box containing petty cash is secured by one combination lock and one keyed lock. One employee is given the combination to the combo lock and another employee has possession of the correct key to the keyed lock. In order to get the cash out of the box both employees must be present at the cash box at the same time. One cannot open the box without the other. This is the aspect of dual control.
On the other hand, split knowledge is exemplified here by the different objects (the combination to the combo lock and the correct physical key), both of which are unique and necessary, that each brings to the meeting.
This is typically used in high value transactions / activities (as per the organizations risk appetite) such as:
Approving a high value transaction using a special user account, where the password of this user account is split into two and managed by two different staff. Both staff should be present to enter the password for a high value transaction. This is often combined with the separation of duties principle. In this case, the posting of the transaction would have been performed by another staff. This leads to a situation where collusion of at least 3 people are required to make a fraud transaction which is of high value.
Payment Card and PIN printing is separated by SOD principles. Now the organization can even enhance the control mechanism by implementing dual control / split knowledge. The card printing activity can be modified to require two staff to key in the passwords for initiating the printing process. Similarly, PIN printing authentication can also be made to be implemented with dual control. Many Host Security modules (HSM) comes with built in controls for dual controls where physical keys are required to initiate the PIN printing process.
Managing encryption keys is another key area where dual control / split knowledge to be implemented.
PCI DSS defines Dual Control as below. This is more from a cryptographic perspective, still useful:
Dual Control: Process of using two or more separate entities (usually persons) operating in concert to protect sensitive functions or information. Both entities are equally responsible for the physical protection of materials involved in vulnerable transactions. No single person is permitted to access or use the materials (for example, the cryptographic key). For manual key generation, conveyance, loading, storage, and retrieval, dual control requires dividing knowledge of the key among the entities. (See also Split Knowledge).
Split knowledge: Condition in which two or more entities separately have key components that individually convey no knowledge of the resultant cryptographic key.
It is key for information security professionals to understand the differences between Dual Control and Separation of Duties. Both complement each other, but are not the same.
The following were incorrect answers:
Segregation of Duties address the splitting of various functions within a process to different users so that it will not create an opportunity for a single user to perform conflicting tasks.
For example, the participation of two or more persons in a transaction creates a system of checks and balances and reduces the possibility of fraud considerably. So it is important for an organization to ensure that all tasks within a process has adequate separation.
Let us look at some use cases of segregation of duties
A person handling cash should not post to the accounting records A loan officer should not disburse loan proceeds for loans they approved Those who have authority to sign cheques should not reconcile the bank accounts The credit card printing personal should not print the credit card PINs Customer address changes must be verified by a second employee before the change can be activated.
In situations where the separation of duties are not possible, because of lack of staff, the senior management should set up additional measure to offset the lack of adequate controls.
To summarise, Segregation of Duties is about Separating the conflicting duties to reduce fraud in an end to end function.
Need To Know (NTK): The term "need to know", when used by government and other organizations (particularly those related to the military), describes the restriction of data which is considered very sensitive. Under need-to-know restrictions, even if one has all the necessary official approvals (such as a security clearance) to access certain information, one would not be given access to such information, unless one has a specific need to know; that is, access to the information must be necessary for the conduct of one's official duties. As with most security mechanisms, the aim is to make it difficult for unauthorized access to occur, without inconveniencing legitimate access. Need-to-know also aims to discourage "browsing" of sensitive material by limiting access to the smallest possible number of people.
EXAM TIP: HOW TO DECIPHER THIS QUESTION First, you probably nototiced that both Separation of Duties and Segregation of Duties are synonymous with each others. This means they are not the BEST answers for sure. That was an easy first step.
For the exam remember:
Separation of Duties is synonymous with Segregation of Duties Dual Control is synonymous with Split Knowledge
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 16048-16078). Auerbach Publications. Kindle Edition. and http://www.ciso.in/dual-control-or-segregation-of-duties/

Section: Network and Telecommunications
Explanation/Reference:
Although it may cause a denial of service to the victim's system, this type of attack is a Smurf attack. A SYN Flood attack uses up all of a system's resources by setting up a number of bogus communication sockets on the victim's system. A Ping of Death attack is done by sending IP packets that exceed the maximum legal length (65535 octets).
Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, chapter 11:
Application and System Development (page 789).

Computer security should be first and foremost cost-effective.
As for any organization, there is a need to measure their cost-effectiveness, to justify
budget usage and provide supportive arguments for their next budget claim. But
organizations often have difficulties to accurately measure the effectiveness and the cost of
their information security activities.
The classical financial approach for ROI calculation is not particularly appropriate for
measuring security-related initiatives: Security is not generally an investment that results in
a profit. Security is more about loss prevention. In other terms, when you invest in security,
you don't expect benefits; you expect to reduce the risks threatening your assets.
The concept of the ROI calculation applies to every investment. Security is no exception.
Executive decision-makers want to know the impact security is having on the bottom line.
In order to know how much they should spend on security, they need to know how much is
the lack of security costing to the business and what
are the most cost-effective solutions.
Applied to security, a Return On Security Investment (ROSI) calculation can provide
quantitative answers to essential financial questions:
Is an organization paying too much for its security?
What financial impact on productivity could have lack of security?
When is the security investment enough?
Is this security product/organisation beneficial?
The following are other concerns about computer security but not the first and foremost:
The costs and benefits of security should be carefully examined in both monetary and non-
monetary terms to ensure that the cost of controls does not exceed expected benefits.
Security should be appropriate and proportionate to the value of and degree of reliance on
the IT systems and to the severity, probability, and extent of potential harm.
Requirements for security vary, depending upon the particular IT system. Therefore it does
not make sense for computer security to cover all identified risks when the cost of the
measures exceeds the value of the systems they are protecting.
Reference(s) used for this question:
SWANSON, Marianne & GUTTMAN, Barbara, National Institute of Standards and
Technology (NIST), NIST Special Publication 800-14, Generally Accepted Principles and
Practices for Securing Information Technology Systems, September 1996 (page 6).
and
http://www.enisa.europa.eu/activities/cert/other-work/introduction-to-return-on-security-
investment