Explanation/Reference:
Explanation:
Authenticity is a close relative of authentication. Authenticity is the process of ensuring that a message received is the same message that was sent and has not been tampered with or altered. Lawyers, as a real-world case in point, are fanatical about ensuring that evidence is authentic and has not been tampered with or altered in any way to ensure a fair hearing for the accused.
Incorrect Answers:
B: Authorization is the rights and permissions granted to an individual (or process), which enable access to a computer resource. Once a user's identity and authentication are established, authorization levels determine the extent of system rights that an operator can hold. This is not what is described in the question.
C: Availability ensures the reliable and timely access to data or computing resources by the appropriate personnel. In other words, availability guarantees that the systems are up and running when they are needed. In addition, this concept guarantees that the security services needed by the security practitioner are in working order. This is not what is described in the question.
D: Nonrepudiation is the assurance that someone cannot deny something. Typically, nonrepudiation refers to the ability to ensure that a party to a contract or a communication cannot deny the authenticity of their signature on a document or the sending of a message that they originated. This is not what is described in the question.
References:
http://www.yourdictionary.com/authenticity

Data validation is a method used to prevent Structured Query Language (SQL) injection attacks, which are a type of web application attack that exploit the input fields of a web form to inject malicious SQL commands into the underlying database. Data validation involves checking the input data for any illegal or unexpected characters, such as quotes, semicolons, or keywords, and rejecting or sanitizing them before passing them to the database34. References: 3: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 6, page 6604: CISSP For Dummies, 7th Edition, Chapter 6, page 199.