In which revision of this sentence are commas used correctly? Mr. Rodriguez is one of the most popular teachers at my school but he soon will move to Phoenix Arizona.

A Mr. Rodriguez, is one of the most popular teachers at my school, but he soon will move to Phoenix Arizona.

B. Mr. Rodriguez is one of the most popular teachers at my school, but he soon will move to Phoenix, Arizona.

c. Mr. Rodriguez is one of the most popular teachers at my school, but, he soon will move to Phoenix, Arizona

D. Mr. Rodriguez is one of the most popular teachers at my school but he soon will move to Phoenix Arizona.

The revision of the sentence in which commas are used correctly is:

B. Mr. Rodriguez is one of the most popular teachers at my school, but he soon will move to Phoenix, Arizona.

Explanation:

The first thing we must keep in mind is that a comma should never separate a subject from its predicate, unless there is an appositive between them. The sentence we are analyzing here has no appositives, which allows us to eliminate letter A for, in it, the comma is placed between the subject and its predicate.

When we have two independent clauses joined by a coordinating conjunction, we should place a comma right before the conjunction. In this case, the coordinating conjunction is "but". That makes letter B the correct option. Letter C is incorrect because it uses another comma immediately after the conjunction. Finally, letter D is also incorrect because it uses no commas at all.

the answer is a).