The correct option is D
It was a project carried out by the United States Air Force, the Royal Air Force, the Royal Canadian Air Force, the Royal Australian Air Force, the Royal Air Force of New Zealand and the South African Air Force. The plan was risky because about four thousand tons of supplies per day seemed impossible by air, but the number of aircraft involved in the airlift grew steadily. The Americans had to be assisted by the rest of their allies, as British and French aircraft also assumed some flight missions. Per year, there were 200,000 flights, with 4,700 tm daily.
