n=3 the electron is in the third energy level (shell).
each sub-orbital can only hold two electrons with the different spin quantum number.
l=2, and means the electron is in the d sublevel (subshell).
m=-1 , represents one of the five 3d orbitals (-2,-1,0,+1,+2).
Two because spin be ± 1/2
Answer: (a)