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 : 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 : ``I Saw What I Saw'' is the sixth episode of the sixth season of the American television medical drama Grey's Anatomy, and the show's 108th episode overall. 
Question : What series is I Saw What I Saw from?

A: series
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Q: Context : Charlie Mars is a vocalist, guitarist and singer-songwriter from Mississippi. 
Question : What was Charlie Mars's occupation?

A:
occupation
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