All the planets in the solar system rotate roughly in a plane that intersects the sun.
Stars in the Milky Way rotate around its centre forming a rough planar disk.
Are these planes all parallel? I.e. Do planets of all stars rotate in planes parallel to the plane of the galaxy? Do they rotate in the same direction?
If so, is it
(a) because the whole galaxy evolved from a spinning mass so it naturally turned out that way
(b) because, over time, the 'wheels' that were spinning on other axes were somehow dragged into alignment
(c) Nobody knows
(d) Something else