Brainliest goes to whoever answers correctly try to show work ONLY if you can also if you want more points answer my other questions

Answer:
It's a function
Step-by-step explanation:
Because the x output does not repeat itself
If it wasn't a function the x would repeat the same
REMEMEBR THE X CAN'T REPEAT IT SELF TWICE WHICH IT IS NOT A FUNCTION
A FUNCTION X HAS TO BE IT SELF LIKE THE NUMBERS CAN'T REPEAT ITSELF.