The correct answer is C: The henry. The unit of inductance is the henry (abbreviated as 'H'), named after Joseph Henry. One henry is a relatively large unit - most inductors are measured in millihenries (mH) or microhenries (μH). Inductance measures how much magnetic flux is created per ampere of current. One henry means the inductor creates one weber of magnetic flux when one ampere flows through it. In practice, you'll commonly see inductors rated in millihenries (thousandths of a henry) or microhenries (millionths of a henry). Understanding the henry as the base unit helps with unit conversions and circuit calculations.