A is the correct answer. If you write out the order pairs of each point the first number is your domain and the second number is your rang. Yes it is a function because your domain does not repeat.
A is the correct answer. A function is defined where every input, x, has only one output. The coordinates are on the graph are (-4,-1), (-1,4), (1,1), and (4,1). As you can see, there is only one output for every input. X is the domain and y is the range.
