Answer:
electrostatic attraction.
Explanation:
As we know those atom donate the electron gets positively charged and those atoms gains the electron gets negatively charged.The charge on the atoms are the responsible for the force in the ionic bond.
We know that force between two charge particle is known as electrostatics force.If charge particle is having same sign charge then it will be repulsive force and If charge particle is having opposite sign charge then it will be attraction force.
Therefore force in the ionic solid is electrostatic attraction.