Read these two excerpts. What do both of these excerpts show?
A
Players with concussions and players who have never injured their brains showed no difference.
B
The scientists could not tell which part of the brain was working during a task.
C
The scientists found that brains had healed within three days of a concussion.
D
Players who have had concussions use more of their brains to complete tasks than they normally would.