Answer: The first option is the correct answer
Step-by-step explanation: It is not a function because it does not pass the vertical line test.
The vertical line test is a test that determines whether or not a relation is a function. To perform the vertical line test you must go through every point and look DOWN the line in which the point lies. If there is another point on the same Y axis then it does not pass the vertical line test which means its not a function.
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