If 30. 34 ml of a 0. 135 m solution of hydrochloric acid (hcl) were required to neutralize 25. 00 ml of a sodium hydroxide (naoh) solution, what is the molarity of the sodium hydroxide solution?.

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

The answer for this is a

The answer is c - the principal of original lateral continuity.