Final answer:
Density is calculated by dividing the mass of a substance by its volume. The Correct Answer is Option. B.
Step-by-step explanation:
The density of a substance is determined by measuring both the mass and volume of the substance, and then calculating the ratio of mass to volume. Therefore, the correct method to determine the density of a substance is found in option D: Measure the mass and volume of the substance, then divide the mass by the volume.
Density has derived units, like g/mL for liquids or g/cm³ for solids. It's important to measure these two properties accurately because the resulting density value is critical in distinguishing between substances and understanding their physical properties.