An Atom of Helium Can Store Energy by Bumping an Electron

Multiple Choice

An atom of helium can store energy by bumping an electron from its lowest orbital energy state to a higher orbital energy level. In particular, moving an electron from the lowest state to the next-lowest state would store an energy of $24.6 \mathrm{eV}$ . Why can we ignore this energy storage mode when calculating the heat capacity of helium gas?

A) This mode is "frozen" out at normal temperatures.
B) Collisions between atoms can't influence the energy levels of electrons inside the atoms.
C) This storage mode is completely independent of the kinetic and/or rotational energy modes.
D) Only modes involving helium molecules count.
E) We have ignored this mode only for simplicity's sake.
F) Some other reason (specify) .