The correct answer is number 2) Japan was prolonging a terrible and bloody war that had an inevitable outcome.
The sentence that best summarizes the Allies reason for using the atomic bomb on Japan was "Japan was prolonging a terrible and bloody war that had an inevitable outcome."
The Allies considered that by dropping the atomic bomb over Japan meant to quickly end World War II. Doing this, there was no need to risk more United States troops in direct confrontation. Some historians said it was a US revenge for the attack of Pearl Harbor. The nuclear bomb was launched over Hiroshima on August 6, 1945, and over Nagasaki on August 9, 1945.