Which of the following practices would be best to prevent an insider from introducing malicious code into a company's development process?

Peer review and approval is the most effective practice because it involves multiple individuals examining code changes before they are integrated. This collaborative approach increases the likelihood of detecting malicious code, backdoors, or logic bombs that an insider might attempt to introduce. It also establishes accountability and acts as a deterrent. While code scanning for vulnerabilities is crucial, it primarily focuses on known vulnerabilities and may not detect intentionally malicious, novel code introduced by an insider. Open-source component usage, while beneficial for development speed, doesn't inherently prevent an insider from adding malicious code to the company's proprietary development. Quality assurance testing focuses on functionality and performance, and while it might uncover issues caused by malicious code, it's not designed to specifically detect malicious intent or hidden backdoors.