The points with coordinates that are do not make sense, since you will not buy and you are buying them a week.

Hi!

Step-by-step explanation:

OPTION C

Step-by-step explanation:

A relation is a function when each input value has one and only output value.

For option A:

 (2,4), (-5, 6), (2, 3), (-6, 2)

You can observe that the input value "2" has two output values. Then it is not a function.

For option B:

(8, 1), (-5, 4), (2, 1), (8, 2)

You can observe that the input value "8" has two output values. Then it is not a function.

For option C:

(2,4), (-5, 2), (8, 1), (-6, 2)

You can observe that each input value has only one output values. Then it is a function.

For option D:

(2,0).(-5, 3), (8, 1), (-5,5)

You can observe that the input value -5 has two output values. Then it is not a function.