Select the sentence that shows correct parallel structure.

a. To do well on final exams, students should not only study every day but also be getting enough sleep.

b. To do well on final exams, students should not only have studied every day but also sleep enough.

c. To do well on final exams, students should not only study every day but also get enough sleep.

The correct answer is letter "C": To do well on final exams, students should not only study every day but also get enough sleep.

Explanation:

Parallel structures are sentences that follow the same pattern of verbs, adjectives, or nouns providing each of them the same level of importance. The statements are connected with a coordinating conjunction that could be: "for", "and", "nor", "or", "but", "so", or "yet".

In the example:

A) To do well on final exams, students should not only study every day but also be getting enough sleep. (Different verb structures)

B) To do well on final exams, students should not only have studied every day but also sleep enough. (Different verb structures)

C) To do well on final exams, students should not only study every day but also get enough sleep. (Parallel verb structures)

Answer: The option that is parallel in structure is option b. To do well on final exams, students should not only have studied every day but also sleep enough.

Explanation: parallel structure is a construct that shows the way similar phrase of Grammer are aligned in a sentence to make it easier for the reader to understand.

Option b is parallel in structure because it has described the student to have studied and slept enough if the student has done well on its final exam. It tells what students who has done well on their final exams did.

Option A and C are not a correct parallel structure because it tells what should be done to do well in a final exam and not what has been done by students who did well. It sounds like an advise to students and not a motivation of what students which has done well did.