instruction:
Classify the relation of question with context to one of these categories: 1) award received, 2) based on, collection, 3) conflict, 4) constellation, 5) convicted of, 6) date of death, 7) director, 8) drafted by, 9) educated at, 10) medical condition, 11) military branch, 12) narrative location, 13) occupation, 14) original network, 15) parent company, 16) point in time, 17) production company, 18) residence, 19) series, 20) service entry, 21) sex or gender, 22) spouse, 23) standards body question.
question:
Context : Princess Helena of Nassau (German: Prinzessin Helene Wilhelmine Henriette Pauline Marianne von Nassau-Weilburg; 18 August 1831 -- 27 October 1888) was a daughter of William, Duke of Nassau (that is, the German state or region referred to as Nassau), and consort of George Victor, Prince of Waldeck and Pyrmont. 
Question : What is Princess Helena of Nassau's spouse's name?
answer:
spouse


question:
Context : Jane Stafford (1899--1991) was an American medical writer and chemist. 
Question : What is the date of Jane Stafford's death?
answer:
date of death


question:
Context : The film was adapted by Wilder and Edwin Blum from the Broadway play by Donald Bevan and Edmund Trzcinski which was based on their experiences as prisoners in Stalag 17B in Austria. 
Question : The Stalag 17 is based upon what?
answer:

based on