Use the source below to answer the question. Primary Source Excerpt: This excerpt is from President Franklin D. Roosevelt’s "Day of Infamy" speech, delivered to Congress on December 8, 1941, following the attack on Pearl Harbor. "Yesterday, December 7, 1941—a date which will live in infamy—the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan. [...] As Commander in Chief of the Army and Navy, I have directed that all measures be taken for our defense." Based on President Roosevelt’s speech, which of the following best explains the immediate effect this speech had on the United States' role in World War II? (4 points) Responses It led to an alliance with Japan to avoid further conflict. It led to an alliance with Japan to avoid further conflict. It marked the United States' entry into World War II as they declared war on Japan the following day. It marked the United States' entry into World War II as they declared war on Japan the following day. It prompted the United States to remain neutral and focus on internal security measures. It prompted the United States to remain neutral and focus on internal security measures. It encouraged Congress to impose economic sanctions on Japan instead of declaring war.

Answer 1

Based on President Roosevelt's "Day of Infamy" speech, the response that best explains the immediate effect this speech had on the United States' role in World War II is:

It marked the United States' entry into World War II as they declared war on Japan the following day.

This option accurately reflects the historical context where Roosevelt's speech served as a pivotal moment that unified the nation and led to the formal declaration of war against Japan after the attack on Pearl Harbor.