a
\(n\) represents the main energy level and / represents the subshell. If \(\mathrm{n}=4\) and \(I=3,\) the subshell is \(4 \mathrm{f}\) If \(f\) subshell, there are \(7\) orbitals and each orbital can accommodate a maximum number of electrons, so, maximum number of electrons in \(4f\) subshell \(=7 \times 2=14\)