If I am going to based it on where did I got earned a lot from them, my answer is the ICO, because way back on 2017 this was the time
were the majority of the community members here in the forum also earned a lot in the ICO, while IEO I got earned but not the same
in the ICO that I joined before, while in the STO and IDO is not yet.
Same, I also get more good results from ICO when entering the fourth quarter of 2017, after that ICO no longer produces and then I tried other luck through IEO, which results are also a little bit bad, but for STOs and IDOs I have never try it.