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.

Input: Consider Input: Context : The Paveway IV entered service with the Royal Navy in 2008. 
Question : Which was the official year for the approval of Paveway IV?

Output: service entry


Input: Consider Input: Context : Timelike Infinity is a 1992 science fiction book by Stephen Baxter. 
Question : What series is Timelike Infinity a part of?

Output: series


Input: Consider Input: Context : Erema; or, my father's sin is a three-volume novel by R. D. Blackmore published in 1877. 
Question : Which place does Erema exist in?


Output: narrative location