3. The table shows the playing time in minutes of high-definition videos and the file size of these videos in megabytes
(MB).
Videos
Playing Time, x
(min)
0.5
1.5
2
4.5
5
File Size, y
(MB)
60
180
240
540
600
What does the slope of the graph of this situation represent?
A. The increase in the file size of the video per minute of playing time
B. The file size of each video
C. The playing time of each video
D. The increase in the playing time per MB of video