Acids are formed when water reacts chemically with oxides halogens metals smog

The correct answer is oxides.
This reaction occurs in the process of making acid rain (rain with elevated levels of hydrogen ions, low pH). Acid rain is produced when emissions of sulfur dioxide and nitrogen oxide, react with the water molecules in the atmosphere to produce acids. For example, nitrogen oxides can be produced by lightning strikes, and sulfur dioxide is produced by volcanic eruptions.