What is the small modification of Bohr's formula for bound-state energies?

A) En = -m2( Ze2/4πε0)2 / n2
B) En = -m2( Ze2/4πε0)2 / n2 + 1
C) En = -m2( Ze2/4πε0)2 / n2 + 2
D) En = -m2( Ze2/4πε0)2 / n2 + 3

This formula can be used for atoms of nuclear charge Ze.