What happens when the width of the picture is changed from 250px to 800px?

Changing the width of the picture from 250px to 800px increases its size, making it larger. In CSS, when you specify dimensions in pixels, you are essentially telling the browser to render the element at that specified width. Thus, when you increase the width from 250px to 800px, the browser allocates more horizontal space for the image, resulting in the image being displayed bigger on the screen.

This is a direct effect of how CSS handles pixel values; since 800px is larger than 250px, this change directly leads to an expansion of the image’s displayed size. The other options do not apply because they suggest outcomes that do not align with the nature of resizing images in a web design context.