I think in the first place will stand Cardano, in second EOS, and in third not yet created at the moment cryptocurrency.
May be! I think! You can see Top 3 coins in 2020 on
https://coinmarketcap.com in top #10
for 2020 very reliable coins we can see starting with development today. because with a coin that is currently experiencing a growing development can make the future much better and profitable. so with the development of current coins are able to bring profits in the future much better in the future. such as Bitcoin, Ethereum, and Ripple.