For which interval is the average rate of change of f(x) negative?

The Average Rate of Change function describes the average rate at which one quanity is changing with respect to something else changing.
 For this case, the first thing you should do is observe the intervals for which the function decreases.
 Remember that the definition of average rate of change is given by:
 
 For AVR to be negative, it must necessarily pass:
 
 The interval that meets both conditions is:
 x = 0 to x = 2.5
 
 x = 0 to x = 2.5
 option 3

The correct answer here is c