The 3rd is the British War medal. Those 3 were given out to everyone who served in the British forces in WWI. The set of three is colloquially known as "Pip, Squeak, and Wilfred" after a popular cartoon.
Victory Medal ("1914-1919: The Great War For Civilization"); the 14 Star (for service in 1914); IDK what the 'British' one would be.
