Complex sentence: With around 100 musicians, the OSO is Ottawa's largest orchestra, which allows it to perform large symphonic repertoire of the 19th and 20th centuries, including works by Canadian composers.
Split into simpler sentences: With around 100 musicians, the OSO is Ottawa's largest orchestra. The OSO specializes in music from the large symphonic repertoire of the 19th and 20th centuries, including works by Canadian composers.