Final answer:
Dependency Scanning is the most effective method to detect security flaws in third-party libraries embedded in software before production release. It checks libraries against known vulnerabilities databases to identify risks. Other methods like Static Code Analysis, Penetration Testing, and Code Review may not be as efficient for this specific purpose.
Step-by-step explanation:
The most effective way to detect security flaws present in third-party libraries before releasing software into production is D. Dependency Scanning. Dependency scanning tools are specifically designed to analyze libraries and dependencies for known vulnerabilities by checking them against databases such as the National Vulnerability Database (NVD). They are efficient in identifying insecure components that might introduce risks into the software. While Static Code Analysis is also valuable in detecting potential security issues within the codebase, it might not always be up-to-date with the latest vulnerabilities specific to third-party libraries. Penetration Testing is performed to simulate an attack on the system and can highlight issues but usually takes place at a later stage of development. A thorough Code Review may find some problems, but due to the complex nature of modern dependencies, it may miss many vulnerabilities that a specialized scanning tool would catch.