The correct option is (a) the neuromuscular function with the neuromuscular blocking drug during general anaesthesia
The best I can explain: In order to allow blood to flow normally, muscles also play an important part. Thus, during surgery, EMG waves are taken to ensure the even spread when a general anesthesia is given. This anesthesia contains neuromuscular drugs so that the pain perception goes down during surgery and so the body does not react when in surgery. If this is monitored properly, it may cause pareses (temporary or permanent loss of muscular function) in future.