the one on the top right is a function.
Step-by-step explanation:
to be a function, each input can have one output. on all the other functions, a number is repeated in the x column which has different a y output. for example, the first one has all inputs of 22.5, but they all have different outputs, meaning it can’t be a function. the table on the top right is the only one that doesn’t have repeated inputs with different outputs.
*just for future reference, different inputs can have the same output. it’s just that the same inputs can’t have different outputs
hope this helped! :)