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.

Context : Abell 754 is a galaxy cluster in the constellation Hydra that was formed from the collision of two smaller clusters. 
Question : Which was the constellation for Abell 754?
constellation

Context : Born on 26 July 1872, Frederick Walshe was educated at Bedford School and at Royal Military Academy, Woolwich. 
Question : What is the university where Frederick Walshe went?
educated at

Context : The Biography of Denis Thatcher by Carol Thatcher (his daughter). 
Question : What is Denis Thatcher's spouse's name?

spouse