When a particle as an electron exist in a box, three quantum numbers are necessary to describe the spatial distributioni fo electrons in atoms. The describe an electron in an atom completely, a fourth quantum number, `m_(s)` called the spin quantum number must be specified. This is because every electron has magnetic moment associated with it which is quantized in one of two possible orientations. Electrons having the same spin strongly repel each other and tend to occupy different region of space. This result of a fundamental law of nature is known as Pauli exclusion principle.
The quantum numbers `+1/2` and `-1/2` for the electron spin represent

Options

A. rotation of the electron in clockwise and anticlockwise direction respectively
B. rotation of the electron in anticlockwise and clockwise direction respectively
C. magnetic moment of the electron pointing up and down respectively.
D. Two quantum mechanical spin states which have no classical analogue

Answer

D