Chemistry · Structure of atom

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).\n Assertion (A): An orbital cannot hold more than two electrons, and these two electrons must have opposite spins.\n Reason (R): According to the Pauli exclusion principle, no two electrons in an atom can have the same set of all four quantum numbers. \nIn the light of the above statements, choose the correct answer from the options given below:

1. A
   Both (A) and (R) are true and (R) is the correct explanation of (A).
2. B
   Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
3. C
   (A) is true but (R) is false.
4. D
   (A) is false but (R) is true.