Question: What opera company has its permanent home as he Staatsoper Unter den Linden and had Franz Betz as an opera singer in the 1800's?
Sentence (from "Franz Betz"): Franz Betz (19 March 1835 – 11 August 1900) was a German bass-baritone opera singer who sang at the Berlin State Opera from 1859 to 1897.
Relevant evidence: Yes