The energy of the electron in a hydrogen atom has a negative sign for hydrogen atom because

Options

A. the energy of the electron in the atom is lower than the energy of a free electron at rest
B. a free electron at rest is an electron that is infinitely far away from the nucleus
C. the energy value assigned to free electron at rest is zero
D. (1),(2) and (3) together forms the valid reason for the given fact

Answer

D