The correct answer to number 17 is C)Japan's dismissal of the Potsdam Declaration.
At the Potsdam Conference, the three major Allied Powers agreed that Japan must submit to an unconditional surrender in order for the war to be over. However, Japan refused to abide by this declaration. This ultimately lead to Truman's decision to use the bombs on Hiroshima and Nagasaki.
The correct answer to number 18 is C) Winston Churchill.
Churchill was a political leader for Great Britain during World War II.
The correct answer to number 19 is D) Let England borrow weapons in the early 1940's.
This was an attempt by the US to help England and the Allied Powers without directly getting involved in the war in Europe.
The correct answer to number 20 is A) Stock Market Speculation.