The electronic configuration together with the quantum number of last electron for lithium is -

Options

A. `1s^(2) 2s ^(1)" "2,0,0 +1/2`
B. `1s ^(2) 2s ^(1) " "2,0,0 + 1/2 or -1/2`
C. `1s ^(2) 2s ^(0) 2p^(1)" "2,1,0 p, 1/2`
D. `2s ^(2) 2s ^(2) " " 2,1,0 pm 1/2 `

Answer

B