Which sentence correctly uses commas to separate items in a list?

the deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the ph level of the paper, and, minimizing the alkaline reserve.
the deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the ph level of the paper and, minimizing the alkaline reserve.
the deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the ph level of the paper, and minimizing the alkaline reserve.
the deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the ph level of the paper and minimizing the alkaline reserve.\