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.
--------
Question: Context : However, in 644, Hormuzan was killed by Umar's son 'Ubaid-Allah, after an involvement in a plot which killed Umar. 
Question : Which war did Hormuzan participate in?

Answer: conflict


Question: Context : In July 1917 Scott was awarded the Military Cross - Capt. (temp Maj.) Alan John Lance Scott Yeo., and R.F.C. For conspicuous gallantry and devotion to duty. 
Question : What army did Alan John Lance Scott serve in?

Answer: military branch


Question: Context : John Houlton Marshall (9 October 1768 in Halifax, Nova Scotia -- 2 May 1837 in Charlotte Street, Bloomsbury Square, Middlesex) was a Nova Scotian who was a naval commander throughout the Napoleonic Wars. 
Question : What army was John Houlton Marshall a part of?

Answer:
military branch