The correct answer is A.
After WWII, the US wanted to promote democracy in Europe, because this was the manner of putting in practice the containment strategy, which was the approach that the US had adopted in foreign policy. It aimed ot stop the spread of communism worldwide.
Propaganda radio programs served the abovementioned purpouse, and also the Marshall Plan. The Marshall Plan was an initiative launched by the US in 1948 to help the recovery of Western European countries after WWII. $ 12 billion were sent to rebuild those countries and to boost their economies by rebuilding factories, infrastructures, civil buildings, etc. After receiving the assistance, Western European powers sided with the US and acted as a barrier for containing communism, that has already suceeded on many Eastern nations of the European continent.