Answer:
British control declined dramatically from 1919 to 2019.
Step-by-step explanation:
In the early 20th century which covered 1919, the British Empire or government-controlled various nations or territories across the world.
From Asia to the American continent, Africa to the Pacific, and Australia, the British Empire were still ruling as colonial masters in many of these territories.
However, by 2019, a hundred years, after the British government or Empire is only left with controlling the territory of Britain and a few islands across the world.
Hence in this case, the correct answer is "British control declined dramatically from 1919 to 2019."