the answer is baking soda. in order to figure out which substance will neutralize the acid you can complete a simple experiment, by combining different mixtures of these items
vinegar and lime juice
lime juice and baking soda
vinegar and baking soda
when combining the vinegar and lime juice, nothing will happen as they are both acidic with a similar ph (between 2-3)
however when you combine either one of these liquids with baking soda, you will find that first you will experience foaming and the creation of lots of bubbles, however once it stops the liquid you are left with is essentially water and will have a relatively neutral ph as baking soda is a base (ph of 9) so once mixed with an acid it neutralizes to a ph of about 7 which is considered neutral.
