which of the following options correctly describe the order in which sublevels (designated by nl) are most commonly filled with electrons? select all that apply. (ignore anomalous electron configurations.) multiple select question. all the sublevels of a given energy level are filled before electrons are placed in the next principal energy level. the 3d orbitals are generally filled after the 4s orbital. the 5f sublevel is filled immediately after the 4d sublevel. the 4d sublevel is filled immediately after the 4p sublevel. the 1s sublevel must be filled before electrons are placed in the 2s orbital.