Answer:
A function cannot have multiple y values for the same x value. Therefore option two is the answer.
Explanation:
Answer option one has different x values and y values so it is a function.
Answer two has the x value -5 for the y value 7 and -4 so it is not a function.
Answer three has different x values and the same y value of 6 for -1 and 5, it is a function.
Answer four has different x values for each but the y value of 2 is used with -3 and 2, it is a function.