Question

the united states formally entered world war ii following the japanese attack on
nanjing
indochina
pearl harbor
the philippines

Explanation:

To determine the correct answer, we recall historical events: the Japanese attack on Pearl Harbor (December 7, 1941) led to the United States formally entering World War II. The attack on Nanjing was a wartime atrocity in China, attack on Indochina was part of Japanese expansion but not the trigger for US entry, and the attack on the Philippines came after Pearl Harbor.

Answer:

C. Pearl Harbor