Final answer:
Systems operation includes two critical steps after the design is completed: systems implementation and systems maintenance, ensuring the system's effectiveness over its operational lifetime.
Step-by-step explanation:
In reference to systems operation within the context provided, the two steps that comprise systems operation are systems implementation and systems maintenance. Therefore, the correct answer is A. systems implementation, systems maintenance. Systems implementation involves the actual creation or development of the system based on the completed design. This may include setting up manufacturing systems, sourcing components, and creating facilities. Following implementation, systems maintenance is crucial to ensure that the system operates correctly over time and continues to meet the required performance criteria.