Final answer:
The displacement of an object must include the measurement from the initial position to the final position and the direction, since displacement is a vector quantity. The correct answer to the question is 'Measurement and direction'.
Step-by-step explanation:
When describing the displacement of an object, you must include both the measurement from the initial position to the final position, and the direction of the displacement. This is because displacement is a vector quantity, which means it has both magnitude and direction. On the other hand, distance only requires the measurement of the total length of the path traveled from the starting position to the ending position, and it is a scalar quantity, having only magnitude without specifying direction.
The correct answer to the question is: a) Measurement and direction. Displacement is defined as the straight-line distance between two points along with the direction from the starting point to the ending point. Unlike distance, which only accounts for the path length, displacement's magnitude is the shortest path between the starting and ending points, and it also takes into account in which direction the change occurred.