Electroencephalography (eeg), in which electrodes placed on the scalp pick up electrical signals underneath, and magnetoencephalography (meg), which detects magnetic indications of brain activity, are examples of what?

Does electrical curents flows of charges across the membrane and the depolarization continues also due to charges that reject each other and the flow continues .so there appears a magnetic field as well

Maybe c? sorry if im wrong

Aform of energy that is reflected or emitted from objects in the form of electrical and magnetic waves that can travel through space. there are many forms of  electromagnetic  energy including gamma rays, x rays, ultraviolet radiation, visible light, infrared radiation, microwaves and radio waves.