which of the following points could be added to the graph to create a square

As an AI language model, I do not have access to any graph or image. Can you please provide more details or information on the graph you are referring to?

To create a square on a graph, each side of the square must have equal length and the corners must form right angles.

Assuming the graph is in the form of (x, y) coordinates, four points that could be added to create a square are:
1. (1, 1)
2. (1, -1)
3. (-1, -1)
4. (-1, 1)

These points form a square with sides of length 2, centered at the origin (0, 0).