Answer:
D. frequency of updates.
Step-by-step explanation:
A wireframe is a simplified and schematic visual prototype of a webpage and is focused explicitly on the skeletal framework (layout, behavior and content) of the webpage. It serves as a blueprint for UX designers and usually does not include any graphics and styling.
Since George is sketching a wireframe representation of the home page of his website. The frequency of updates aspect of the home page would be impossible to represent in this diagram because it's not part of the elements of a website wireframe.