In this question, we have a reaction between silver nitrate and potassium chloride, which will have the following chemical formula and also the following product:
AgNO3 (aq) + KCl (aq) --> AgCl (s) + KNO3 (aq)
Now we need to identify the ions that are components of the precipitate that was formed in this reaction
A precipitate is a product of a reaction that is not soluble in water in the conditions given in the reaction, therefore the precipitate will be a solid product of the reaction. The solid of the reaction is AgCl, therefore this is the precipitate
Now the ions that compose AgCl are Ag+ and Cl-, the answer will be the 3rd option
