In which scenario should the manual lift method be used?

The manual lift method should indeed be used when no other rescue methods are available. This approach is often designed for situations where quick and immediate action is necessary, especially when traditional rescue tools or methods cannot be deployed effectively or safely. The manual lift allows rescuers to move a victim in a basic and urgent way, facilitating transport to a safer location or to emergency medical assistance when other options are not feasible.

In contrast, the other scenarios describe situations that may not warrant the immediate use of manual lifting. For example, if the victim is unconscious, this may complicate the manual lift due to the risk of injury or additional complications arising from improper handling. If both the bucket and the victim are stable, utilizing mechanical or alternative rescue methods could be safer and more effective; stability in these elements might allow for a better approach. Lastly, under emergency conditions, while the manual lift can be a valid option, it's also important to assess whether safer alternatives exist that can be executed. Thus, the correct answer emphasizes the necessity to resort to manual lifting only when absolutely required.