Explanation:

The slope of a distance-time graph represents the rate of change of distance with respect to time. This means that it represents how fast an object is moving over time. The slope is calculated by dividing the change in distance by the change in time.

- Speed: The slope of the distance-time graph gives the speed of the object. This is because speed is defined as the distance traveled per unit time. Therefore, the slope represents the speed of the object at any given time.
- Acceleration: The slope of the distance-time graph does not give the acceleration of the object. Acceleration is the rate of change of velocity with respect to time. The distance-time graph only gives information about the distance traveled by the object, not its velocity.
- Distance: The slope of the distance-time graph does not give the distance traveled by the object. The distance traveled is represented by the area under the curve of the graph.
- Displacement: The slope of the distance-time graph does not give the displacement of the object. Displacement is the change in position of an object in a particular direction. The distance-time graph only gives information about the distance traveled, not the direction of the movement.

Therefore, the correct answer is option 'C', which states that the slope of the distance-time graph represents the speed of the object.