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 : Christopher Drew Carter (born September 5, 1981) is a former American football wide receiver of the National Football League. 
Question : What is the name of university that educated Drew Carter?
educated at

Context : Norway - Upgraded to NASAMS 2. 
Question : Which was the official year for the approval of NASAMS?
service entry

Context : Virtually all battles that are considered part of the 'Battle of the Border' (with the exception of the Battle of Hel, which lasted for more than a month and the Battle of Mokra, a Polish defensive victory) resulted in rapid defeat of Polish forces, which were forced to abandon the regions of Pomerania, Greater Poland and Silesia. 
Question : When did Battle of the Border occurr?

point in time