The reason salt crystals, such as KCl, hold together so well is because the cations are strongly attracted to:
a
neighboring anions.
b
free electrons in the crystals.
c
neighboring cations.
d
the protons in the neighboring nucleus.
The answer is anions. Cations are positively-charged ions (in this case K+) while anions are negatively-charged ions (in this case Cl-). The ions attract each other through electrostatic charges and arrange themselves in an ordered fashion to form a lattice
