What do you think is most likely to exist: Space aliens visiting Earth, Loch Ness Monster, or Bigfoot?

Loch Ness is merely a creature that could have existed at one time, so that has some likelyhood to it. Same with Bigfoot, it's possible that there really is a creature described like Bigfoot. I can't say it's true, but there is some likelyhood. Aliens visiting from Space? Well that seems impossible because it would require probably the ability to travel faster than the speed of light, and the existence of highly advanced life on another planet, probably in a distant star system. There are too many credible eye witnesses of UFO's or flying saucers,to really say that they don't exist, but it seems less credible when people claim that they have seen alien creatures coming from inside the UFO after a landing. So I think Bigfoot or Loch Ness are more likely. Bigfoot seems to be backed up with some reality, because there are many legends, and even parts of the Bible where giant humans "Nephilim" are mentioned.