A biologist is tracking the total population of birds in a national park. Over a 20-year period, the rate of change of the population went from −6,500 per year to 4,200 per year. Which stateme best describes this change?
A. The rate of change increased by 10,700 per year.
B. The rate of change decreased by 10,700 per year.
C. The rate of change increased by 2,300 per year.
D. The rate of change decreased by 2,300 per year.