I think the correct answer from the choices listed above is option C. The correct format would be:
According to John Smith, the most common error in solving math questions "relates to the order of operations (9)."
For MLA format, quotations are enclosed within double quotation marks, the author is provided and the specific page. It should be noted that there should be no period after the parenthetical citation.
Well, Emiliano Zapato was a hero from mexico. He was a leading figure in the Mexican revolution. He was the inspiration for the agrarian called Zapatismo.