When Is an Atom in Its Ground State

When is an atom in its ground state?

A) when the electrons of the atom are in the lowest possible energy levels
B) when an atom loses all of its electrons to form a noble gas
C) when the electrons of the atom are in the highest possible energy levels
D) when an electron is promoted to a higher energy level,farther from the nucleus
E) when the electrons of an atom spontaneously emit energy in the form of a photon