I'm disappointed in some of the responses here. Far too pessimistic and nihilistic for my taste. The bad things about humanity (and there are plenty, major historical setbacks like wars, the dark ages, genocides, etc.) are balanced by good things (family, friends, science, technology, art, music, the constant long timescale trend of reduction of suffering... PerlMonks!). I'm not particularly religious myself, but it's the classic dichotomy of good vs. evil if you will.

Besides that, it took human intelligence developing to the point it has to understand well enough to even ask the big questions. The whole "humans are the problem, if we didn't exist everything would be great" notion is self contradictory, if there were no human intelligence around there would be nobody to even ask the big questions, let along make the assessment between what's "good" and what's "bad", it's a paradox of higher-order consciousness and self awareness. You can always find bad things in the world if you go looking, often truly awful, terrible things like war, disease, famine, etc. If you focus on those things (like the news unfortunately tends to) the world can look pretty grim, and it's easy to get mired in that outlook, but if you step back and look at it on a grander scale over a long period of time, the general trend of good things is increasing and the general trend of bad things is decreasing. More so now than ever!

But to answer the question of the poll itself, World Peace can most likely be achieved by humanity continuing to progress, little by little, year on year, despite all the stumbles and occasional backtracking along the way, just like we always have. With that in mind, and "other" not being an option, I didn't even vote.

Seriously, things are going great, and they're only getting better. But don't take my word for it...

https://www.amazon.com/Enlightenment-Now-Science-Humanism-Progress/dp/0525427570

https://humanprogress.org/

https://twitter.com/HumanProgress?ref_src=twsrc%5Egoogle%7Ctwcamp%5Eserp%7Ctwgr%5Eauthor

All the metrics, charts, and studies in the book tell a promising (and very grounded in reality) tale. If you constantly feel pessimistic about the world and you use Twitter, my first recommendation would be to stop using Twitter (I kid, I kid... well, I partly kid anyway), but short of that at least add that last one to your feed. :-)