Final answer:
To safely transfer a person with a full-sling mechanical lift, at least d. 4 workers are needed.
Step-by-step explanation:
When using a full-sling mechanical lift to transfer a person, the correct option is d. 4 workers are needed.
A full-sling mechanical lift is used to safely transfer individuals who have limited mobility or are unable to bear weight on their own. It consists of a sling that supports the individual's body and a mechanical device to lift and move them.
To ensure the safety and comfort of the person being transferred, it is recommended to have at least four workers involved in the process.
Each worker will have a specific role: two workers will assist in supporting the person and securing the sling, one worker will operate the mechanical lift, and one worker will provide additional support and assistance as needed.