This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
What are the EEG waves record for parietooccipital region with subject awake & eye closed? 
Select and explain. 
A. Alpha waves, B. Beta waves, C. Delta waves, D. Theta waves
A: Alpha waves
Answer: A: Alpha waves 
Explanation: In adult humans who are awake but at rest with the mind wandering and eyes closed the most prominent component of EEG is a fairly regular pattern of waves at a frequency of 8-13 Hz and amplitude of 50-100uV, this pattern is the alpha rhythm. Ref: Ganong&;s review of medical physiology; 23rd edition; pg:233