Context : Michael Osborne Waddell MC (22 December 1922 - 22 May 2015) was a British Army officer of the 50th Royal Tank Regiment who won an immediate Military Cross for his actions during the invasion of Sicily in 1943 when he saved the lives of eleven men after his column was hit by enemy fire. 
Answer : British Army
Which military branch is Michael Osborne Waddell a part of?