The sentence that correctly uses commas to separate items in the list is number 3, "The deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the pH level of the paper, and minimizing the alkaline reserve."
There are three things that preserve pages in the deacidification process:
Therefore, these three items make up are list. Commas are used after every item in a list. However, a comma is not needed after the last item in a list. Of the available options only, number 3 uses the commas in the correct places as seen below:
"The deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the pH level of the paper, and minimizing the alkaline reserve."
Technically, number 4 could also be correct. An Oxford comma is the last comma in a list. Some people choose to not use the Oxford comma. It is generally accepted as correct, although it can sometimes cause confusion when not used. The elimination of the Oxford comma can be seen below:
The deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the pH level of the paper and minimizing the alkaline reserve.
Answer:
The sentence that uses commas correctly is 3. The deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the pH level of the paper, and minimizing the alkaline reserve.
Explanation:
In English, when we need to separate items in a list, we place a comma between each one of them. The last item in the list is usually introduced by the coordinating conjunction "and". We still need to place a comma before "and", but we should not place one after it. Let's study a simple example:
- I asked Jane to buy apples, oranges, grapes, and bananas.
The same should happen in the sentence provided in the question. We have three items to separate:
1. neutralizing acid with magnesium oxide;
2. raising the pH level of the paper;
3. minimizing the alkaline reserve.
In the sentence, those items must have a comma between them. The last one is introduced by "and", having a comma before but not after it. Therefore:
3. The deacidification process preserves pages by neutralizing acid with magnesium oxide, raising the pH level of the paper, and minimizing the alkaline reserve.
