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.

[Q]: Context : Gelnhausen railway (Hungen--Gießen) was opened on 29 December 1869 and Hungen station went into operation. 
Answer : 29 December 1869
[A]: When was Hungen station opened?


[Q]: Context : Avanade Inc. was founded in 2000 as a joint venture between Accenture and Microsoft to serve an untapped market for Microsoft-focused consulting services. 
Answer : Accenture
[A]: Which company is the parent company of Avanade?


[Q]: Context : Vampires vs. Zombies is an independent horror film loosely based upon J. Sheridan Le Fanu's classic 1872 novel Carmilla. 
Answer : Carmilla
[A]:
The Vampires vs. Zombies is based upon what?