VSEPR question

[gsingh2011]

The question is: Which species has exactly five pairs of electrons around
the central atom?
(A) ClF5 (B) SF4 (C) SF5– (D) XeF4

The answer is B. Can someone explain why? I'm not too good with these geometries that use the d-orbital.

[DrDu]

There are no d orbitals involved. You just have to count the number of valence electrons. In the first example there are 7 electrons from Cl and 5 from Fluorine, i.e. 12 in total or six pairs. Analogously for the other cases.