When an electron moves from the ground state to the excited state:
a) it emits energy and moves farther from the nucleus.
b) emits energy and moves closer to the nucleus.
c) absorbs energy and moves closer to the nucleus.
d) absorbs energy and moves farther from the nucleus.

d) absorbs energy and moves farther from the nucleus.

Explanation:

Absorption is the phenomenon whereby the energy of a photon is taken by a particle, like an atom, whose valence electrons take this energy, moving from a lower level (ground state) to a higher level (excited state) of electronic energy, moving away from the atomic nucleus.

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.