Question: What group of prominent 19th Century composers were Alexander Borodin and Mily Balakirev apart of?
Sentence (from "The Mighty Handful"): Mily Balakirev (the leader), César Cui, Modest Mussorgsky, Nikolai Rimsky-Korsakov and Alexander Borodin all lived in Saint Petersburg, and collaborated from 1856 to 1870.
Relevant evidence: Yes