Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.

Ex Input:
Context : Mainova AG was formed in 1998 through the merger of Stadtwerke Frankfurt am Main GmbH and Maingas AG. 
Answer : Stadtwerke Frankfurt

Ex Output:
What is Mainova's parent company?


Ex Input:
Context : William George Bock (born June 11, 1884 in Port Elgin, Ontario, Canada-died 1973) was a Canadian politician and farmer. 
Answer : 1973

Ex Output:
What year did William George Bock die?


Ex Input:
Context : Caterina Sforza (1463 -- 28 May 1509), was an Italian noblewoman and Countess of Forlì and Lady of Imola firstly with her husband Girolamo Riario, and after his death as a regent of her son Ottaviano. 
Answer : Girolamo Riario

Ex Output:

What is Caterina Sforza's spouse's name?