Final answer:
The advantage mentioned is associated with Peripheral Nerve Stimulation (PNS) only.
Step-by-step explanation:
The advantage mentioned in the question is associated with Peripheral Nerve Stimulation (PNS) only.
PNS refers to the stimulation of peripheral nerves to produce a desired effect, such as pain relief. It is used in medical treatments like nerve block, where local anesthetics are injected to block pain signals.
On the other hand, ultrasound is a medical imaging technique that uses sound waves to create images of the body. It is not directly related to the safety or blocking effect mentioned in the question.