A. Providing advice over the telephone requires clinical judgment and assessment, which are beyond the scope of practice for assistive personnel (AP). This task should not be delegated. B. Inserting an NG tube is an invasive procedure that requires advanced training and skill, so it is not within the scope of the AP. This task must be performed by a nurse or another licensed provider. C. Teaching a client how to walk on crutches involves instruction and monitoring, which requires the clinical judgment and teaching skills of a nurse or physical therapist, making it unsuitable for AP delegation. D. Performing a simple dressing change is a routine and basic task that can be safely delegated to an AP, as long as the task does not require sterile technique or complex wound care.