Concept:Little Boy was the codename for the first atomic bomb used in warfare, a fission bomb.
Explanation:It was dropped on Hiroshima, Japan, on 6 August 1945 by the US B-29 bomber Enola Gay.
It released approximately 15 kilotons of TNT energy, causing massive destruction.
The bomb used uranium-235 in a gun-type fission design.
It was the second man-made nuclear explosion (after the Trinity test) but the first used in combat.
This distinguishes it from the plutonium-implosion bomb "Fat Man" dropped on Nagasaki.
Answer:Option A: The fission bomb dropped at Hiroshima