It's a signup scam. The "survey" asks for your name, home address, and cell phone number. Then they spam you with a half dozen pages of ads, and finally it demands that you sign up for one of three offers before the "survey" is over. If you don't sign up with any of the offers, you can't finish it. I reported it to mTurk. Very surprised to see this garbage from a big name like CrowdFlower.