Answer:
Last possible answer is the correct one.
Step-by-step explanation:
The graph of a function shows that for any input (x), there is ONLY one output (y). The fourth and last answer option is the only one that satisfies this requirement.
Note that you could also apply the vertical line test to determine whether the graphs represent a function or not. If a vertical line drawn through the graph intersects the graph ONLY once, then the graph represents a function.
