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.

[Q]: Context : The United Defense M42, sometimes known as the Marlin for the manufacturer, was an American submachine gun in World War II. It was produced from 1942 to 1943 by United Defense Supply Corp. (a government-formed company specifically tasked with weapons development) for possible issue as a replacement for the Thompson submachine gun and was used by agents of the Office of Strategic Services (OSS). 
Question : In what year did United Defense M42 enter service?
[A]: service entry


[Q]: Context : Lida, Princess Victor of Thurn and Taxis (née Lida Eleanor Nicolls), also referred to as Princess Lida of Thurn and Taxis, (1875 -- 6 December 1965) was an American millionairess, socialite, and the wife of Prince Victor of Thurn and Taxis. 
Question : What is Princess Lida of Thurn and Taxis's spouse's name?
[A]: spouse


[Q]: Context : Grandfather Stories is a book of 23 historical tales by journalist and novelist Samuel Hopkins Adams. 
Question : Which place does Grandfather Stories exist in?
[A]:
narrative location