Which of the following is the BEST method a security practitioner can use to ensure that systems and sub-systems gracefully handle invalid input?
Correct Answer: C
Negative testing is the best method a security practitioner can use to ensure that systems and sub-systems gracefully handle invalid input. Negative testing is a type of software testing that involves providing invalid, unexpected, or erroneous input to the system or sub-system, and verifying how it responds or handles the input. Negative testing can help to identify and eliminate bugs, errors, exceptions, and vulnerabilities in the system or sub-system, and to ensure that it does not crash, freeze, or behave unpredictably when faced with invalid input. Negative testing can also help to improve the security, reliability, and usability of the system or sub-system, and to ensure that it meets the functional and non-functional requirements34. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 10, page 882; 100 CISSP Questions, Answers and Explanations, Question 17.