Please solve these questions from the picture provided.

Are there any options?

Answer is to avoid experimental error

The real answer is keeping the world healthy so we won’t die

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.