Answer
The legitimate set of quantum numbers therefore is
a) 1, 0, 0
b) 2, 0, 0
d) 2, 1, +1
Work Step by Step
Following are the constraints of the quantum numbers:
1) Possible value of $n$ can be only a natural number.
2) Possible value of $l$ depends on $n$ and is in the range $0$ to $n-1$.
3) Possible value of $m_l$ depends on $l$ and is in the range $-l$ to $l$.
The legitimate set of quantum numbers therefore is
a) 1, 0, 0
b) 2, 0, 0
d) 2, 1, +1
