An element with positioning is removed from the normal flow and keeps its position even when the user scrolls.

An element with fixed positioning is removed from normal flow and keeps its place constant or even when user scrolls. This kind of positioning is fairly uncommon but truly has its uses of its own. A fixed role detail is placed relative to the viewport, or the browser window itself. The viewport would not exchange when the window is scrolled, so a set positioned element will stay proper in which it is when the page is scrolled, creating an impact a bit just like the antique college days.

Ithink it is letter b, i may be wrong but i think that is the answer