Generate a correct and concise answer for the question based on the words in the context.

[EX Q]: Context : The 18th Mounted Brigade previously known as the 2/1st Yorkshire Mounted Brigade was a 2nd Line yeomanry brigade of the British Army during the First World War. 
Question : To which branch did 18th Mounted Brigade belong?
[EX A]: British Army

[EX Q]: Context : Major General Courtney Whitney (May 20, 1897 - March 21, 1969) was an American lawyer and Army commander during World War II who later served as a senior official during the occupation of Japan. 
Question : Which conflict was Courtney Whitney a part of?
[EX A]: World War II

[EX Q]: Context : The first Valemax vessel, Vale Brasil, was delivered in 2011. 
Question : In which year was the service entry date for Valemax?
[EX A]:
2011