ubiquity - Why do I have so many options in install? What do I pick?

I have a windows 8 desktop and I'm trying to install Ubuntu. In my computer on windows I see two drives (C: for windows and D: empty)

When I try to install Ubuntu, there's a big list of options of which drive to pick. What do I pick?

In the first image, it's the list of options showing in the "Device for boot loader installation" menu. In the second image, it's showing the main window with the list of drives. What drive do I pick? I want to install Ubuntu on the D:.