Explanation:

Here’s the thing:

- Option 1: Speed—This is how fast something is moving, regardless of direction. On a velocity-time graph, speed is the magnitude of velocity, but the area under the graph doesn’t give you speed itself.

- Option 2: Displacement— This is the total change in position, considering direction. The area under a velocity-time graph between two time points directly gives you displacement.

- Option 3: Velocity—This is the rate of change of position. The graph itself represents velocity at each instant, not the area under the curve.

- Option 4: Acceleration—This is how quickly velocity changes. On this graph, it would be the slope at any point, not the area under the curve.

So, the answer is Option 2, Displacement—the area under the velocity-time graph tells you exactly how far (and in what direction) an object has moved.