Joules is the SI units for work.
Answer: Option D
Step-by-step explanation:
In the metric system, which is a common nomenclature for the standard representation of measurements to avoid confusions and errors, the unit of work is joule.
Work is referred as the amount of energy spent by a force. SI stands for International system of units. Option A,B and C are irrelevant because watts is used to represent power, and calories are used to represent the energy spent.