What is the fifth phase in the defense acquisition life cycle?

• A. Engineering and Manufacturing Development
• B. Requirements analysis
• C. Materiel Solution Analysis
• D. Operations and Support

Answer: (D)

The main idea here is the lifecycle flow from defining a need to delivering a system and then keeping it effective over time. After early work to analyze needs and explore possible solutions, and after maturing technology and completing system development and demonstration, the program moves into producing and deploying the system. The fifth phase is Operations and Support, which centers on sustaining the fielded system throughout its life. This includes maintenance, supply and logistics, training, repairs, upgrades, and overall support to ensure performance is maintained while controlling life-cycle cost. The earlier stages—requirements analysis and Materiel Solution Analysis—happen before fielding, and the development phase (including Engineering and Manufacturing Development) and Production and Deployment occur before Operations and Support, so that phase ordering places Operations and Support last.