A zoologist is studying the behavior of a cheetah on an African plain. The zoologist recorded the cheetah's running speed and displayed it in the graph below.
Cheetah's Speed Over Time
70
50
Speed (miles per hour)
30
10
5
45
55
15 25 35
Time (seconds)
Which of the following BEST describes a functional relationship shown in the graph?
A
The cheetah is running faster at the 50-second mark than at the 10-second mark.
B
The cheetah increased its speed for a total of 40 seconds.
C
The cheetah's speed remained constant for the last 15 seconds.
D
The cheetah spent a longer time increasing its speed than decreasing its speed.