What feature allows the web page to respond dynamically to user actions?

The feature that allows a web page to respond dynamically to user actions is a scripting language. Scripting languages enable the creation of interactive experiences by allowing developers to write code that executes in response to user inputs, such as mouse clicks, keyboard inputs, or other events. This dynamic functionality can include updating content, validating forms, animating elements, and more, all of which help enhance user engagement.

On the other hand, markup languages are primarily designed to structure and present content, without the capabilities for user interaction. Static HTML refers to a fixed structure that does not change unless modified manually, meaning it lacks interactivity. Email protocol is unrelated to web design and does not pertain to how a web page behaves in response to user actions.