Section: Information System Acquisition, Development and Implementation

Section: Information System Operations, Maintenance and Support

Explanation/Reference:
It is important to read carefully the question. The word "incorrectly" was the key word. You had to find which one of the definitions presented is incorrect. The definition of Accountability was NOT properly described. Below you have the proper definition.
The correct definitions are as follows
Authenticity - A third party must be able to verify that the content of a message is from a specific entity and nobody else.
Non-repudiation - The origin or the receipt of a specific message must be verifiable by a third party. A person cannot deny having sent a message if the message is signed by the originator.
Accountability - The action of an entity must be uniquely traceable to that entity Network availability - The IT resource must be available on a timely basis to meet mission requirements or to avoid substantial losses.
The following reference(s) were/was used to create this question:
CISA review manual 2014 Page number 34

Trojan horses are malicious or damaging code hidden within an authorized computer program. Hackers use Trojans to mastermind DDOS attacks that affect computers that access the same Internet site at the same moment, resulting in overloaded site servers that may no longer be able to process legitimate requests. Logic bombs are programs designed to destroy or modify data at a specific time in the future. Phishing is an attack, normally via e-mail, pretending to be an authorized person or organization requesting information. Spyware is a program that picks up information from PC drives by making copies of their contents.

Explanation/Reference:
Explanation:
The security level of a private key system depends on the number of encryption key bits. The larger the number of bits, the more difficult it would be to understand or determine the algorithm. The security of the message will depend on the encryption key bits used. More than keys by themselves, the algorithm and its complexity make the content more secured. Channels, which could be open or secure, are the mode for sending the message.