Final answer:
Stimulation of the A1 area of the auditory cortex by Penfield typically resulted in the perception of simple tones, as this area is principally involved in processing basic auditory information such as pitch.
Step-by-step explanation:
Stimulation of the A1 area of the auditory cortex by Penfield produced C) simple tones. The A1 area is responsible for processing basic sound elements such as pitch and volume rather than complex sequences such as speech or words. When Penfield stimulated this region while patients were under local anesthesia, they were able to report the experience of hearing simple sounds, not words or voices, which are processed in other areas of the cerebral cortex, like Wernicke's and Broca's areas associated with speech comprehension and production respectively.