To determine which function has an inverse that is also a function, we use the Horizontal Line Test. A function passes this test if no horizontal line crosses the graph more than once. If a function passes this test, its inverse will also be a function.

Let's analyze each graph:

1. Top-left graph: This graph fails the horizontal line test because a horizontal line will intersect it more than once at several places.
2. Top-right graph: This graph passes the horizontal line test. Any horizontal line will intersect it at only one point, meaning its inverse will also be a function.
3. Bottom-left graph: This graph fails the horizontal line test as a horizontal line can intersect it at more than one point.
4. Bottom-right graph: This graph also fails the horizontal line test. A horizontal line will intersect it in two places at many points.

Conclusion: The top-right graph is the one that has an inverse that is also a function.

Would you like more details or have any questions?

Here are 5 related questions for further learning:

1. What does it mean for a function to be "one-to-one"?
2. How can you determine if a function is invertible from its equation alone?
3. What is the algebraic process to find the inverse of a function?
4. Can functions that fail the horizontal line test be modified to have inverses?
5. How does the concept of domain restriction affect the invertibility of functions?

Tip: Always apply the horizontal line test before finding the inverse of a function to ensure the result is also a function!