The graph shows the velocity f(t) of a runner during a certain time interval: Graph of line segment going through ordered pairs 0, 4 and 4, 8. Graph of another line segment going through ordered pairs 4, 8 and 8, 0. Label on the x axis is time in seconds, and label on the y axis is velocity in meters per second.

Which of the following describes the intercepts on the graph?
a. The initial velocity of the runner was 4 m/s, and the runner stopped after 8 seconds.
b. The initial velocity of the runner was 8 m/s, and the runner stopped after 4 seconds.
c. The initial acceleration of the runner was 4 m/s2, and the runner stopped after 8 seconds.
d. The initial acceleration of the runner was 8 m/s2, and the runner stopped after 4 seconds.