You just started X for the first time and noticed that the display does not use the entire screen.
What program can you use to fix this?

A.
xvidtune

B.
xf86config

C.
XF86Setup

D.
tweakscreen

Explanation:
xvidtunE. video mode tuner for XFree86.
Synopsis: xvidtune [ – show | -prev | -next | -unlock ] [ -toolkitoption … ]