Which of the following is the SI base unit for mass?

• A. pound (lb)
• B. tonne (t)
• C. kilogram (kg)
• D. gram (g)

Answer: (C)

Verified step by step guidance

1. Understand that the International System of Units (SI) defines base units for fundamental physical quantities, including mass.
2. Recall that the SI base unit for mass is the kilogram (kg), which is the standard unit used worldwide in scientific measurements.
3. Recognize that the gram (g) is a derived unit equal to 1/1000 of a kilogram, so it is not the base unit but a subunit of mass.
4. Note that the pound (lb) is a unit of mass used primarily in the imperial system, not part of the SI system.
5. Identify that the tonne (t) is a metric unit equal to 1000 kilograms, also not a base unit but a multiple of the kilogram.