Which current regularly reverses its direction?

• A. Direct current
• B. Alternating current
• C. Galvanic current
• D. High Frequency

Answer: (B)

Alternating current is the type of electrical current that regularly reverses its direction. In AC, the flow of electrons changes back and forth in a repeating pattern (typically a sine wave), so the direction switches many times per second. This contrasts with direct current, which moves in one constant direction. Galvanic current is a direct current used in some modalities, so it does not reverse direction. High frequency is a form of alternating current with rapid oscillations, but the essential idea described by the question is captured by alternating current, the current that reverses direction regularly.