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 : For decades only Episode 3 of The Enemy of the World was known to have survived erasure, but the five missing episodes were announced as recovered by the BBC on 11 October 2013 along with four of the missing episodes of the following serial, The Web of Fear. 
Question : To which series does The Enemy of the World belong?

A: series
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Q: Context : Erik Bruhn died in Toronto General Hospital on 1 April 1986 at the age of 57. 
Question : What sex is Erik Bruhn?

A: sex or gender
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Q: Context : 15 Arietis (abbreviated 15 Ari) is a single variable star in the northern constellation of Aries. 
Question : The star 15 Arietis is part of what constellation?

A:
constellation
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