What did the atomic bomb achieve that conventional military force had not yet done?
a. eliminated japan's entire naval force
b. forced the japanese to surrender
c. destroyed japan's oil reserves
d. forced the japanese to retreat from china

Correct answer choice is :

President Harry S. Truman, advised by some of his authorities that any effort to attack Japan would appear in horrific American fatalities, directed that the new weapon is used to take the war to a quick end. On August 6, 1945, the American plane Enola Gay released a five-ton bomb over the Japanese city of Hiroshima. Hiroshima was preferred because it had not been targeted during the US Air Force's current bombing attacks on Japan, and was therefore considered as being a proper place to test the results of an atomic bomb. It was also an essential army camp.