I have an old Minolta Maxxum 7000 camera and 50mm lens (photos below). I would like to mount the lens on my Canon 5D Mark II. Is this adapter the one I need?
No, that would not be the correct adapter. The Maxxum 7000 was the first camera to use Minolta's new A-mount; quoting from Wikipedia:
[The Maxxum 7000] introduced a new lens mount, the A system, breaking compatibility with its earlier manual-focus lenses in the MC and MD system.
Unfortunately, it's not quite possible to make a glassless A to EF adapter, so you'd need a significantly more expensive adapter which contains glass.