Final answer:
An RN in an eye and ear clinic can delegate the task of checking a patient's visual acuity with a Snellen chart to an LPN/LVN, as this task involves basic data collection within the LPN's scope of practice.
Step-by-step explanation:
The action that a registered nurse (RN) working in an eye and ear clinic could delegate to a licensed practical/vocational nurse (LPN/LVN) is using a Snellen chart to check a patient's visual acuity. Clinical tasks such as evaluating a patient's ability to administer eye drops and teaching a patient about using sodium fluoride and vitamin D for otosclerosis are typically reserved for RNs due to the evaluative and educational components that require a more advanced scope of practice. However, LPNs/LVNs can competently perform tasks that involve basic data collection and reporting, like checking for signs of irritation caused by a hearing aid or conducting a vision test using the Snellen chart.