Actually, the answer is B "the development of the hydrogen bomb" :)
Are you wondering which president it was? It was John Adams in 1798.
The candidate had to be trained as a scholar and then pass a series of written examinations. The Chinese civil service system, established in 124 B.C.E., required potential officials to be trained as scholars and then pass rigorous examinations to qualify for office.
The correct answer is A. Pay interest on savings accounts.
They use your money to give out loans and when people pay the loan back with interest, they take the interest and split it between themselves and your account because you were helpful to them.