Given is the electronic configuration of element X:

K   L   M   N 

2   8   11   2

The number of electrons present .with l = 2 in an atom of element X is :

Correct option is A)

Given K  L   M   N 

           2   8  11   2 

The number of electrons present in l = 2 is- 3.
The electronic configuration is$1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^{6}3{\mathrm{d}}^{3}4{\mathrm{s}}^2$
$l=2$corresponds to $3\mathrm{d}$ subshell which contains $3$ electrons.