Which care task should a charge nurse delegate to an assistive personnel in a long-term care unit?

The most appropriate task for a charge nurse to delegate to assistive personnel in a long-term care unit is measuring urine output every 2 hours for a client with a urinary tract infection. This task involves observing and recording the quantity of urine output, which is a straightforward and objective measurement that does not require analysis or clinical judgment. Assistive personnel are trained to perform tasks that involve basic care and monitoring, making this an ideal assignment for them.

The other options involve more complex or clinical tasks that require nursing judgment and assessment skills. Assessing lung sounds and administering medications involve analyzing patient conditions and making decisions based on the findings, which is beyond the scope of practice for assistive personnel. Performing a full assessment on a new admission requires comprehensive clinical skills and knowledge, typically performed by registered nurses to ensure a thorough evaluation of the patient's needs and condition.