"Which of the following is correctly punctuated? As you may know, information chips are already encoded in the visas of people who need them for work, travel or study in this country. As you may know, information chips are already encoded in the visas of people who need them for work, travel, or study in this country. As you may know information chips are already encoded in the visas of people who need them for work, travel or study in this country."

As you may know, information chips are already encoded in the visas of people who need them for work, travel, or study in this country.

Explanation:

The sentence above is correctly punctuated. The comma is used appropriately in the sentence. Commas are used to separate independent clauses especially when there is a conjunction joining them such as but, or, yet, so.

Example: 1) Yesterday was my daughter's birthday, so I took her out to dinner.

               2)  I left the house early enough, but I still didn't meet up for the    meeting.

Commas can also be used after the first clause or phrase in a sentence.

Example: While I was eating, the alarm clock rang.

                 After the test, we left for home.

Commas are used to separate three or more words. They are used to itemize things in a sentence.

Example ; She bought some oranges, apples and paw-paw for her uncle last week.

As you may know, information chips are already encoded in the visas of people who need them for work, travel or study in this country.

Explanation:

Punctuation is the use of set of markers in a sentence, phrase, linking words or set of words listed as an item to regulate and clarify them for easier reading and understanding. With punctuation markers, it is easy to clarify meanings in utterances as they aid or give room for  proper understanding.

Examples of punctuation marks include: the coma, colon, semicolon, apostrophe, full stop or period, question mark, exclamation point, the dash and hyphen, braces, parentheses, quotation marks and ellipsis.

The above sentence has been punctuated correctly as it separates the first part of the sentence with a coma indicating a separation of the idea in the structure of the sentence. The coma is used to separate words or numbers written in a sentence as shown above where it separates the words ''work and travel''. A full stop or period is used at the end of the sentence which indicates completion or end of the sentence.

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