Answer:
A. If none of the output values are repeated, the relation is a function
Explanation:
The reason why A is correct stems from the concept of the vertical line test. If each x-value has their own respective output (y-value), then the relation is a function.
Choice B just states that if none of the x-values are repeated. then the relation is a function. This is not correct because it doesnt follow the vertical line test, which analyzes if any y-values are being repeated
Choice C and D doesnt have any correlation with the vertical line test because an x-value doesnt have to equal a y-value to make the relation a function. Vice versa for any y value being equal to any x-value.