The orbital angular momentum for an electron revolving in an orbit is given by $\sqrt{l(l+1)} \frac{h}{2 \pi} $. The momentum for an s-electron will be given by :

Question

( A ) $\frac{h}{2 \pi}$
( B ) zero
( C ) $\sqrt{2}. \frac{h}{2 \pi}$
( D ) $+\frac{1}{2}.\frac{h}{2 \pi}$