I don't really know the easiest survey to work from, because survey in general never worked for me at all. I'm keeping on the low with surveys. It depends on your demographic, to land a better offer from surveys. Consider it, if you're from 1st world countries, your chances of landing a high and easy surveys are high. But when you're from 3rd, 4th world countries your chances becomes slim. Cos of the low advertisers that comes from those countries. Surveys direct their offers mainly on 1st and 2nd world countries. But you can still try
http://surveytime.io they are worldwide, they offer surveys to any body.