SI units — practice question

Which expression, written in SI base units, is equivalent to the volt?

• A$\text{kg m}^2\,\text{s}^{-1}\,\text{A}^{-1}$
• B$\text{kg m s}^{-2}\,\text{A}$
• C$\text{kg m}^2\,\text{s}^{-1}\,\text{A}$
• D$\text{kg m}^2\,\text{s}^{-3}\,\text{A}^{-1}$