Which ions in flint water caused the protective layer inside the pipes to break down? question 2 options: 1.oxgyen ions 2.lead ions 3.iron ions 4.chlorine ions

The answers to this question are oxygen and chloride ions. In this chemical reaction, two proccesses are involved: oxidation and reduction.Oxidizing agents found in water can react with lead pipes leading to the contamination of supply. Lead dissolves with the water and does not stick with the pipe.And also, Flint water has high concentrations of chlorine. This further accelerated the corrosion of pipes.
 

What is the question