Final answer:
The correct nursing action when applying a heating pad to a client with neck pain is to keep the pad in place for 20 to 30 minutes and assess it regularly to prevent burns or irritation, covering it with a light towel.
Step-by-step explanation:
The question is regarding the proper nursing actions when applying a heating pad to a client experiencing neck pain. The correct nursing action from the options provided is C) The nurse keeps the pad in place for 20 to 30 minutes, assessing it regularly. This is because it is essential to monitor the client's skin condition and comfort frequently to prevent burns or irritation that can be caused by excessive heat. In addition, the heating pad should be covered with a cloth cover or a light towel rather than a heavy blanket that can over-insulate and increase the risk of burns (Option A is incorrect). The heating pad should not be placed under the client, as direct pressure can increase the risk of burns (Option B is incorrect). Lastly, using a safety pin can damage the heating pad or the cover and is a potential safety hazard (Option D is incorrect).