Static analysis is a method of analyzing software code without executing it, by using tools or techniques that check for syntax errors, logic errors, vulnerabilities, coding standards, and other quality issues. Static analysis can help software developers to correct the error-handling capabilities of an application before pushing it to production, as it can detect potential errors and bugs at an early stage of development. A web-application vulnerability scan (A) is a method of testing web applications for security flaws by simulating attacks and analyzing responses. It can be useful for finding vulnerabilities in web applications, but not for validating the error-handling capabilities of an application. A packet inspection is a method of monitoring network traffic by examining the data packets that are sent and received over a network. It can be useful for detecting malicious or unauthorized activity on a network, but not for validating the error-handling capabilities of an application. A penetration test (D) is a method of evaluating the security of a system or network by simulating real-world attacks and exploiting vulnerabilities. It can be useful for assessing the overall security posture of a system or network, but not for validating the error-handling capabilities of an application.