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.

Ex Input:
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 occur?

Ex Output:
point in time


Ex Input:
Context : Maa Exchange is a Hindi language Indian reality television series which premiered on January 12, 2011 on Sony TV. 
Question : What production company or companies created Maa Exchange?

Ex Output:
production company


Ex Input:
Context : The T-35 was developed by the OKMO design bureau of the Bolshevik Factory, which began work on a heavy tank in 1930. 
Question : What year did T-35 come into use?

Ex Output:

service entry