The range of a function is the set of values that the function reach with its outputs.
In other words, a number [tex] y [/tex] belongs to the range of the function [tex] f [/tex] if there exists a number [tex] x [/tex] belonging to the domain of [tex] f [/tex] such that [tex] f(x)=y [/tex].
Looking at your graph, you can see that any value smaller than 2 is not reached by the graph, because the lines are only drawn from 2 upwards.
So, the answer is C, because it is the set of all numbers greater then or equal to 2.
