None of those are good IMO, though if I had to choose I'd go with Spears. Paltrow really? The coloring is a train wreck. Not to mention, I think the head size is way off on all of them. I honestly wouldn't make any of them public.
I posted them as a funny example of how different fakers can use one and the same original pic. I have no idea if those artists keep in touch with eath other, or compete, but such sets can illustrate some trends in the world of fakes. I call them "body sharing".
As for the head size, I do not think that they inserted the celebrities' heads, they only pasted their faces. And the clue is the hairstyle which differs only a little bit from pic to pic. They had to change some locks, yes, but they did not touch the original model's head.