Which statement describes the acid found in vinegar (acetic acid)?

Answer : It reacts with Mg to produce .

Explanation : Acid which is present in vinegar is approximately 5 % of acetic acid. This can be confirmed by testing the vinegar with magnesium. Which gives out hydrogen as a gas. Also, it changes blue litmus to red which shows the presence of acid compound. It releases H+ ions in the solutions. Which confirms the presence of acid in vinegar.

all of the above is the answer :)