Final answer:
An EEG records the brain's electrical impulses using electrodes placed around the head to measure electrical activity, which is valuable for various research applications including sleep studies. Option C is correct.
Step-by-step explanation:
An EEG, or electroencephalography, is a method used to record the electrical impulses from the brain.
This technique involves placing an array of electrodes around a person’s head to receive signals that represent the brain's electrical activity.
The EEG provides a measure of the brain's electrical activity showing the frequency and amplitude of the brainwaves with high temporal resolution. This information is invaluable for research in areas such as sleep patterns and brain disorders. So Option C is correct among the given options.