If the solution process is exothermic, then an increase in temperature usually results in:

an increase in solubility

a decrease in solubility

no change in the solubility

a nonpolar solution precipitating most of its solute

a decrease in solubility

Explanation:

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle.

This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.  

If a reaction is exothermic reaction in which heat is released in the reaction.

If in the equilibrium system, temperature is increased, so according to the Le-Chatlier's principle , the equilibrium will shift in the direction where decrease in temperature occurs. As, the backward reaction is a endothermic reaction, backward reaction will decrease the temperature.

Hence, the equilibrium will shift in the backward direction and thus solubility will decrease.

they are all solids.