Basically all three of Roma, City and CSKA have 5 points. Assuming Bayern beats CSKA, it all comes down to the encounter between Roma and City, the one who wins advances. In case of a draw, away goals are important:
0:0 -> Roma advance
1:1 or more goals -> City advance due to better goal difference.
Of course, if they draw, and CSKA somehow beat Bayern, they're both out, which would be quite hilarious