In which system is human intervention often required to achieve desired outputs?

The correct answer identifies the open loop system, which operates without feedback to adjust its performance. In an open loop system, the control actions are set based on predetermined inputs or conditions, and there is no mechanism to monitor the output or make adjustments in real-time. This means that if the desired outcome is not achieved, human intervention is necessary to assess the situation and make corrective actions.

For example, consider a basic heating system that runs for a fixed amount of time regardless of the temperature of the room. If the desired room temperature is not achieved, someone must manually adjust the heater or the timing to reach the correct temperature. This reliance on human input to troubleshoot and adjust the system is characteristic of open loop systems.

Other types of systems, such as closed loop and control systems, incorporate feedback mechanisms that allow them to adjust automatically in response to output conditions, minimizing the need for human intervention. An iterative system may also adjust based on previous outputs but does so through repeated cycles rather than needing immediate human input. Thus, open loop systems distinctly require human involvement to ensure the desired outputs are achieved when the initial commands do not suffice.