1. Because I love the helmet + face shield.
But 4. would be the best.
On an unrelated note - Why the hell are they wearing earphones and it's not even placed on their ears? Did you know those are used so you don't go deaf shooting all day? So if they're animal girl's with a better sense of hearing, why on Earth are they not on properly?
Hell, some of them don't even have headgear or ear protection. Going with 4. because they look prepared. The others may as well be cosplayers with their wack setup. 4. has some ear protection. Not much, but more than the others by far.