Path A: Wales would defeat Austria and Ukraine would do the same against Scotland. And after a Wales - Ukraine matchup, Wales would manage to qualify for the World Cup.
Path B: Russia would beat Poland and Czech Republic would do it to Sweden. And after a Russia - Czech Republic matchup, Russia would manage to qualify for the World Cup.
Path C: Portugal and Italy would succeed in defeating their opponents. And after a Portugal - Italy matchup, Italy would manage to qualify for the World Cup.
Here in third we have most talked match is going to be played between the very good and talented teams Portugal vs Italy so here mostly people's favoring Italy but still anybody game.
I think that Ukraine would advance in case we see a Wales - Ukraine game. They are more powerful than their opponent when it comes to scoring and they would make use of it nicely. And I'm not so sure about the Russia - Poland one. Poland might advance with the help of Lewandowski maybe. And for the last path, I agree with @Spack17 totally.