Which of the following states that two electrons can occupy the same orbital only if they have opposite spins? hund’s rule dalton’s theory aufbau principle debroglie’s theory pauli exclusion principle

The correct option is PAULI EXCLUSION PRINCIPLE.

Pauli exclusion principle states that two electrons in an atom or a molecule can not have the same four electronic quantum number. Each atomic orbital can accommodate maximum of two electrons which have opposite spins. The spins usually have some values attached to them. An orbital with two spins in opposite direction is a filled orbital and the orbital will not be able to accommodate another one except one of those inside is removed.