Which of the following commands is used to start a service using SYSTEMD?

The command used to start a service in a system that utilizes the SYSTEMD initialization system is "systemctl start." This command interacts directly with the SYSTEMD manager to control the state of services, enabling administrators to start, stop, restart, or check the status of services efficiently.

SYSTEMD has become the default system and service manager in many modern Linux distributions, replacing older systems like SysVinit. The "systemctl" utility is the primary interface for managing these services. When you execute "systemctl start [service_name]," you are telling the system to initiate the specified service, allowing it to run and perform its designated tasks.

It's important to note that the other options do not correspond to valid commands for starting services under SYSTEMD. "systemctl begin" is not a recognized command, nor is "service start," which pertains to older systems that used SysVinit. Similarly, "init start" is not a command associated with SYSTEMD, as "init" relates more to the traditional init systems. This distinction highlights the importance of using the correct command suite when managing services in a SYSTEMD environment.