(A) ** Japanese attack on Pearl Harbor.
(B) German invasion of Poland.
(C) German invasion of the Soviet Union.
(D) Italian invasion of Ethiopia.
EXPLANATIONS BELOW
Concept note-1: -On December 7, 1941, following the Japanese bombing of Pearl Harbor, the United States declared war on Japan. Three days later, after Germany and Italy declared war on it, the United States became fully engaged in the Second World War.
Concept note-2: -Japan intended the attack as a preventive action. Its aim was to prevent the United States Pacific Fleet from interfering with its planned military actions in Southeast Asia against overseas territories of the United Kingdom, the Netherlands, and those of the United States.
Concept note-3: -The Japanese attack on Pearl Harbor on December 7, 1941, ended the debate over American intervention in both the Pacific and European theaters of World War II. The day after the attack, Congress declared war on Imperial Japan with only a single dissenting vote.
Concept note-4: -The Japanese attack on Pearl Harbor on December 7, 1941, was the impetus for the United States’ entrance into World War II. The United States declared war on Japan the following day, December 8. On December 11, Nazi Germany, Japan’s Axis ally, declared war on the United States.