Answer:
C.
There is no repeated x or y values
We know that a relation is a function, when each input of x value gives exactly one output of y-value.
In a function two or more x-coordinates can give same y-value, but one x-value cannot give two y-values.
We can see that in our given set each x-value corresponds to exactly one y-value, therefore, the given set represents a function.
Step-by-step explanation: Hopefully this helped, if not HMU and I will get you a better answer
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