According to best practice, which of the following is required when implementing third party software in a production environment?

Scanning third-party applications for vulnerabilities before production deployment is a foundational secure software supply chain practice. It identifies known CVEs, misconfigurations, or malicious code embedded in the software before it can compromise the production environment, aligning with frameworks like NIST SP 800-53 and the OWASP Software Component Verification Standard.

While vendor patching contracts can be beneficial, they are a vendor management consideration and not a universally required security prerequisite before deploying software into production.

End-user training is an operational and change-management concern that improves adoption but does not address the security requirements for safely introducing third-party software into a production environment.

Software escrow protects against vendor insolvency by storing source code with a third party, but it is a business continuity measure rather than a security prerequisite for production deployment.