From the graph shown, the function appears to be a parabola, which opens downwards.

To determine if the function is one-to-one, we use the horizontal line test. A function is one-to-one if and only if every horizontal line intersects the graph at most once. Looking at the graph, a horizontal line (for example, at $y = 5$) would intersect the parabola at two points. This indicates that the function is not one-to-one.

Thus, the correct answer is:

No, there is a horizontal line that intersects the graph at more than one point.

Would you like a more detailed explanation or have any questions?

Here are 5 related questions to deepen your understanding:

1. What is the vertical line test used for?
2. How can we algebraically verify if a function is one-to-one?
3. What is the significance of the inverse function in relation to one-to-one functions?
4. Can a quadratic function ever be one-to-one? Why or why not?
5. How does the horizontal line test relate to the concept of injectivity in mathematics?

Tip: Remember, if a function passes the horizontal line test, it has an inverse that is also a function.