The systems support and phase begins when a system becomes operational and continues until the system reaches the end of its useful life.

Security

Explanation:

The SDLC or system development life cycle is a process of which all systems must go through from planning to the end of the system.

Implementation of system requires creating the system based on the planned design, once it is implemented, it is verified by testing the system. The security of the system prevent intruders from accessing the system from the verification of the functionality to the end of the system's life cycle.

answer; the correct answer is (operating system);

that without the operating systems you would have to control and synchronize computer hardware.