Each answer choice below represents a relation by a set of ordered pairs. In which of the answer choices is the relation a function? Select all correct answers.

Select all that apply:

{(4,9),(0,−2),(0,2),(5,4)}
{(5,−5),(5,−4),(7,−2),(3,8)}
{(4,3),(8,0),(5,2),(−5,0)}
{(6,9),(9,−4),(6,1),(−5,11)}
{(4,12),(2,6),(−5,6),(3,−2)}