Using a visual tracing tool, how can you determine if a function is continuous at x = 3?

Trace the graph at x = 3 without lifting the pen. If you can do so, the function is continuous at that point.

Ensure the graph is symmetric around x = 3.

Check if the graph has a vertical tangent line at x = 3.

Verify that the graph has a horizontal tangent line at x = 3.