There Is Evidence That People Under Surgical Anesthesia Occasionally Hear

There is evidence that people under surgical anesthesia occasionally hear and remember comments that were made during their surgeries.What does this evidence suggest

A)  There is no difference between conscious and unconscious processes. 
B)  Psychic abilities are more pronounced when certain types of drugs are administered. 
C)  We have the ability to resist the effects of anesthesia. 
D)  People continue to maintain some awareness during times of unconsciousness.