The correct option is A 6
Given,
|ml|=1 means ml can be +1 and -1.
Since n = 4, the possible values of `l' are 0,1,2 and 3.
For, l=0 the orbitals of required ml value are not possible.
For the rest of the sub shells we will get a total of 6 orbitals having ml values +1 and -1.
So 6 orbitals can accomodate maximum of 12 electrons according to Pauli's exclusion principle. Since we are considering only +12 spin, thus we will get 6 electrons only.