What decision allows entry into the production and deployment phase?

Milestone C is indeed the decision point that allows a project to enter the production and deployment phase. At Milestone C, the system has successfully passed through earlier phases, including development and testing, and has demonstrated that it is ready for full-scale production. This milestone is critical as it confirms that the system meets the required performance and reliability standards and that it is suitable for deployment to users.

Reaching Milestone C signifies that the project has gone through thorough evaluations, including performance assessments and risk management checks, ensuring that the system can be produced at scale. It also indicates that adequate plans for operational support and sustainment have been established, making it a pivotal step in the acquisition lifecycle.