Electr/o refers to which concept?

• A. Electricity
• B. Energy
• C. Magnetism
• D. Charge

Answer: (A)

Electr/o is a combining form that signifies electricity—the electrical phenomena and things related to it. In medical terms, this root shows up in words that describe electrical activity or devices in the body, such as electrocardiography or electrode. So the concept it conveys is electricity, not energy in general, magnetism, or the abstract idea of charge. Energy is broader, magnetism deals with magnetic effects, and charge is a property of particles; electr/o specifically points to electricity and electrical activity.