All of the Following Are Problems That a Researcher Needs

All of the following are problems that a researcher needs to keep in mind when their research uses methods of looking at brain activity to find areas of brain localization

A) Seeing that an area is active to a given response could mean that it is indeed the center responsible for that activity or it could mean that it was the area their technique focused on and another brain region is actually more important.
B) If a region responds to stimulation it is difficult to tell if that region is necessary or sufficient for that activity. Perhaps it is sufficient only if other parts are also involved.
C) If a PET scan finds increased glucose consumption in response to a stimulus it is hard to decide if this is because that region is important to that activity or if that region is damaged and, as a result, requires more glucose to do minimal processing.
D) Many regions of the brain contain mirror neurons that fire with considerable activity when other regions fire even though their firing has no functional connection to the first region's activity.