Final answer:
The source describes the attack on Pearl Harbor on December 7, 1941, which led to the United States entering World War II after declaring war on Japan, Germany, and Italy. The correct option is A.
Step-by-step explanation:
The excerpt provided describes the event when the United States was "suddenly and deliberately attacked by naval and air forces of the Empire of Japan" on December 7, 1941. This day, which President Franklin D. Roosevelt referred to as "a date which will live in infamy", is most directly associated with the attack on Pearl Harbor by the Japanese empire.
This surprise assault led to the United States officially entering World War II following a declaration of war on Japan, and consequently, war against Germany and Italy, adhering to their alliance obligations.
Hence, Option A is correct.