Which of the following is a primary function of fuzz testing software?

Fuzz testing software is primarily designed to supply invalid inputs, either randomly or systematically, to applications in order to identify potential vulnerabilities and software weaknesses. This technique helps uncover issues such as buffer overflows, input validation errors, and other security flaws that could be exploited by malicious users. By bombarding the application with unexpected or erroneous data, fuzz testing can reveal how the software responds under abnormal conditions, allowing developers to address vulnerabilities before the application goes into production.

The other options focus on different aspects of software operation or evaluation. Running applications in production relates to deployment and does not pertain to testing methodologies like fuzz testing. Measuring execution speed is about performance assessment rather than security testing, while checking for compliance with regulations involves ensuring that software meets specific legal or industry standards, which is outside the primary scope of fuzz testing.