We are presented with a group of graphs in which the x-axis represents time and the y-axis represents speed.
We are told that Joy started by accelerating when she took off, which means the graph should start with a line with positive slope.
She then maintained her speed, which means the slope of the line is 0, orin other words, the line is parallel to the time axis.
Finally, we are told that she saw a sign saying the speed limit had been increased, so she probably accelerated again, meaning the line should have a positive slope again.
Thus, the graph representing the situation is the third option.