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.
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Question: Context : Wolfgang Kretzschmar (2 July 1907 -- 27 December 1944) was a German officer serving during World War II and recipient of the coveted Knight's Cross of the Iron Cross with Oak Leaves and Swords (German: Ritterkreuz des Eisernen Kreuzes mit Eichenlaub und Schwertern). 
Question : In which war did Wolfgang Kretzschmar serve?

Answer: conflict


Question: Context : Joshua James Guppey (August 27, 1820 -- December 8, 1893) was a military officer in the Union Army during the American Civil War, judge, school superintendent and politician. 
Question : What was the war that Joshua James Guppey fought in?

Answer: conflict


Question: Context : Fritz X was a nickname used both by Allied and Luftwaffe personnel. 
Question : What year did Fritz X come into use?

Answer:
service entry