Understand Unit Cube Concept Practice Test

In the 3D model, Cube A has edges labeled 1 unit, 1 unit, and 1 unit. Cube B has edges labeled 2 units, 2 units, and 2 units. Unit cubes are used to measure volume because they show how many cubic units fill a space. Which claim about these cubes is incorrect?

Look at the 3D model of a box shape built from unit cubes. Each unit cube has edge length 1 unit, so each one fills 1 cubic unit of space. Unit cubes are used to measure volume. Which statement about using unit cubes to measure volume is correct?