Mass may be measured in which of the following?

The correct answer is determined by understanding the units of measurement relevant to mass. The unit 'kg,' which stands for kilograms, is the standard metric unit used to quantify mass. It is widely used across various scientific and engineering disciplines to measure the amount of matter in an object.

In contrast, the other options represent different physical quantities:

• 'kJ' stands for kilojoules, a unit of energy, which does not provide a measure of mass.

• 'Kelvin' is a unit used to measure temperature, not mass.

• 'N/m' (Newtons per meter) is a unit of measurement typically related to force per unit length, which also does not pertain to the measurement of mass.

Thus, the only appropriate and correct unit for measuring mass from the options provided is kilograms (kg).