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 : William de St Croix was educated at Eton and St John's College, Cambridge, graduating in 1843. 
Question : What university did William de St Croix attend?

A: educated at
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Q: Context : After Attila's death in 453 AD, his Empire crumbled and its remains were ruled by his three sons, Ellac, Dengizich and Ernak. 
Question : On what date did Ellac die?

A:
date of death
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