Final answer:
The most appropriate method to teach a patient with severe cognitive deficits to comb their hair using a functional skills training approach is to repeat the task sub-steps with fading cues.
Step-by-step explanation:
The most appropriate method to use in teaching a patient with severe cognitive deficits to comb their hair using a functional skills training approach would be option C: Repetition of the task sub-steps with gradually fading cues.
This method involves breaking down the task of combing hair into smaller sub-steps and providing cues to guide the patient through each step. Initially, the cues can be more explicit, but over time, they can be faded or made less obvious as the patient becomes more independent in performing the task.
For example, at first, the OTA may provide step-by-step verbal instructions and physically guide the patient's hand through the motions of combing their hair. As the patient becomes more familiar with the task, the OTA can gradually reduce the amount of verbal instructions and physical guidance, allowing the patient to perform the task more independently.