Answer :
The Manhattan Project was a secret U.S. project to develop nuclear bombs. The correct option in respect to the given question is option "B". During the second World War, the Manhattan Project was a research and development project aimed towards making the first nuclear bomb. It had the support of two other countries and they were Canada and United Kingdom. This project had other dimension to it as well, like gathering information regarding the nuclear project of the Germans. Although the Manhattan project was initially very small, but later on it employed around 130000 people.