Answer:
A function is a special type of relation for which there is a rule that pairs each input with exactly one output.
Step-by-step explanation:
Functions have input (x) and output (y). For each x value there can only be one y value. :) repeating x values means it isn't a function. its okay to have repeating y values.
We can cancel out the last two for this reason above ^^^^ the second choice is wrong because i say so (=^w^=)
