Confidentiality is the prevention of the intentional or unintentional unauthorized disclosure of contents. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 60.

The Diffie-Hellman algorithm is used for Key agreement (key distribution) and cannot be used to encrypt and decrypt messages.
Source: WALLHOFF, John, CBK#5 Cryptography (CISSP Study Guide), April 2002 (page
4).
Note: key agreement, is different from key exchange, the functionality used by the other asymmetric algorithms.
References:
AIO, third edition Cryptography (Page 632)
AIO, fourth edition Cryptography (Page 709)

Explanation/Reference:
Explanation:
A Pseudo flaw is appearing as a vulnerability in an operating system program but is in actual fact a trap for intruders who may attempt to exploit the vulnerability.
Incorrect Answers:
B: Pseudocode is an informal high-level description of the operating principle of a software program. It uses some of the syntax and conventions of a programming language, but is intended for human reading rather than machine reading.
C: Bounds checking is used to test for violations in application programming. Essentially, it tests the application's response to inputted data and ensures the inputted data are of an acceptable length.
D: A page fault is caused when the operating kernel attempts to access a page that is in virtual memory rather than in RAM. This often causes the system to halt.
References:
http://itlaw.wikia.com/wiki/Pseudo-flaw
https://en.wikipedia.org/wiki/Pseudocode
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 334 Conrad, Eric, Seth Misenar and Joshua Feldman, CISSP Study Guide, 2nd Edition, Syngress, Waltham,
2012, p. 267