A fourth way to connect a C128 to modern hardware is with a VGA adapter. A widely known model, the GBS-8220, unfortunately is not friendly to the C128. See my webpage if you want to hear me bash the GBS. But here I will simply say that a direct connection will not work. You need at the very least a circuit to mix the C128's H-Sync and V-Sync into a so-called "composite sync". Even if you do that, you will only get 8 colors! That is unless you buy a "Video DAC" (try this link) or build one yourself (shown below).
RGBI/H/V -> RGBa/C schematic:
And here are some screen shots. First a simple "color bar" in standard text mode (640x200):
And finally an interlaced-video (640x459) text screen from the ZED text editor: