What does animation in web design create?

The correct choice illustrates how animation in web design effectively creates the illusion of motion. By using a sequence of still images that change rapidly, web designers can simulate movement. This technique is pivotal in engaging users, drawing attention to crucial elements, and enhancing storytelling on a webpage. It allows for a dynamic user experience, making websites feel more lively and interactive.

The other options focus on different aspects of web design. The interactive menu responding to mouse movements is a form of interactivity rather than a specific animation technique. A static layout enhances usability but does not involve animation at all. Similarly, transitions between different sections of a webpage may involve animation, but they represent a narrower application of the broader concept of creating the illusion of motion. Hence, the first choice encapsulates the essence of what animation achieves in web design.