Answer:
The correct answer is: Maintenance Phase.
Step-by-step explanation:
In the Systems Development Life Cycle (SDLC) the maintenance phase is the stage where the information system is in use, system enhancements and modifications have been developed and tested, and components of hardware and software have been added or replaced. The previous system used is still valid only to ensure a smooth transition towards the new one and it also serves as a backup in front of unexpected failures.