Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.

Input: Consider Input: Context : George Armistead (April 10, 1780 -- April 25, 1818) was an American military officer who served as the commander of Fort McHenry during the Battle of Baltimore in the War of 1812. 
Answer : Battle of Baltimore

Output: What war or battle involved George Armistead?


Input: Consider Input: Context : The 106th Regiment of Foot (Black Musqueteers) was an infantry regiment of the British Army from 1761 to 1763. 
Answer : British Army

Output: What armed force was 106th Regiment of Foot (Black Musqueteers) in?


Input: Consider Input: Context : OPML (Outline Processor Markup Language) is an XML format for outlines (defined as ``a tree, where each node contains a set of named attributes with string values''). 
Answer : XML


Output: Which is the basis of OPML?