The United States entered WWII because Japan bombed Pearl Harbor, Hawaii which is answer A.
Originally, the United States was not planning to join the war and we only contributed by giving supplies to the Allies to help keep Britain and other countries going. But once we were bombed by Japan, it was the last straw and we joined the war.
I hope that helps!
The correct answer is C) they trained British pilots in effective air support techniques.
<em>U.S. pilots contributed to the allied war effort in Europe during World War II in that they trained British pilots in effective air support techniques.
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Air warfare during World War II was a key element in the strategies and tactics of the battles that the Allied Forces and the Axis Powers fought. The United States Air Force and Great Britain army deployed air strategies for bombing raids over important targets in Germany such as its main cities. Air superiority was an important advantage to win the war in the air.
The other options of the question were, a) they carried out countless bombing raids over German cities, b) they sank ships carrying supplies to Britain, and d) they ferried retreating troops between Britain and Europe.
