<span>These nonessential elements, which can be words, phrases, or clauses, are set off with commas. Rule: Use commas before and after nonessential words, phrases, and clauses, that is, elements embedded in the sentence that interrupt it without changing the essential meaning.</span>
I would say that plate tectonics shows what the origin of volcanic activity, earthquakes and mountains comes from their collision or subduction. Where two plates collide mountains can be formed (uplift), where subduction occurs then volcanic activity like in the circum-pacific belt occurs and where stresses build up in subduction or transform fault (like the San Andreas Fault) and are suddenly released, earthquakes are the result. Subduction is where the oceanic plate gets pushed under the continental plate.
What are the answer choices
The answer is 2, because they introduce his doings similarly, by using "And" and "A".
You should avoid Fictional writing
