A security code reviewer is setting up an environment for an organization that can analyze third-party libraries. Which type of environment should the reviewer set up?

Setting up a sandbox environment is ideal for analyzing third-party libraries, as it offers a controlled and isolated space for testing and evaluation. This environment allows security code reviewers to safely execute and analyze the behavior of potentially untrusted code without risking the stability or security of the organization's primary operational systems.

A sandbox is specifically designed to enable experimentation and the testing of new or unverified software. By using a sandbox, the reviewer can monitor the libraries for vulnerabilities, assess their behavior, and identify any potential security issues without the threat of harmful interactions affecting other environments or live applications.

In contrast, a development or production environment is typically used for more stable code that is already trusted and has been through several rounds of testing. These environments do not provide the same level of isolation needed for thorough testing of unverified third-party libraries. A QA environment, while focused on testing, also may not offer the same degree of safety and isolation that a sandbox does for the purpose of analyzing potentially insecure or untrusted code. Thus, the sandbox is the most appropriate choice for ensuring that testing is done safely and effectively.