An unknown substance is added to a solution and the ph decreases. the substance is best described as

Since there is the same amount of agn03 in both silver chloride and silver nitrate they produce the same amount of moles. therefore silver chloride produces the same amount of silver nitrate, so your answer is 15.0 moles of silver nitrate. i hope this !

The answer is b because c don't explain why the moths are on them and it isn't a because as we know only one species of moth does this