Correct Answer: Brain

Solution : The correct option is Brain.

Electroencephalography, or EEG, is a test that detects electrical activity in the brain. It is used to diagnose a wide range of neurological illnesses, including epilepsy, sleep problems, and brain tumours. EEG may determine brain activity by monitoring the electrical impulses produced by brain cells. Because these impulses are so faint, they are amplified and recorded using an electroencephalograph. The recordings are then shown on a computer screen or a strip of paper. Various waves of brain activity correspond to various brain activities. Alpha waves, for example, are associated with comfortable awareness, beta waves with concentrated concentration, and delta waves with profound sleep.