Match the following rules with their statements.

Explanation

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A. Hund's rule states that paring of electrons in the orbitals belonging to the same subshell (p,d or f) does not take place until each orbital belonging to that subshell has got one electron each ie., it is singly occupied.
B. Aufbau principle states that in the ground state of the atoms, the orbitals are filled in order of their increasing energies.
C. According to Pauli exclusion principle, no two electrons in an atom can have the same set of four quantum numbers.
D. Heisenberg's uncertainly principle states that it is impossible to determine the exact position and exact momentum of a subatomic particle simultaneously.