Which statement correctly describes monophasic current?

• A. It provides a unidirectional current
• B. It alternates direction with each half-cycle
• C. It is always high frequency
• D. It uses symmetrical biphasic waveforms

Answer: (A)

Monophasic current means the current flows in one direction during each pulse, delivering a single polarity without reversal. That unidirectional flow is why the statement is correct: the pulse has only one phase of a given polarity and does not invert direction within the pulse.

If the current reversed direction with each half-cycle, you’d be looking at biphasic or alternating current, not monophasic. Frequency alone does not define monophasic current—it can be delivered at various frequencies, so saying it’s always high frequency isn’t accurate. And “symmetrical biphasic waveforms” describe a different mode entirely, where equal and opposite phases occur within each pulse.