What change was made in the second sentence?
The boy never considered himself to be an excellent student, yet recently he had focused on his studies and received good grades.
The boy never considered himself to be an excellent student. Yet recently, he had focused on his studies and received good grades.
added a prepositional phrase
changed sentence length
inverted subject-verb order
created a compound sentence

The change that was made in the second sentence is the sentence length. The initial sentence is actually a compound one that contains two independent clauses joined by a comma. Therefore, omit the last option. The position of subject and verb in a sentence did not change at all, the only thing that makes difference now is that sentence has been divided into two new ones. So the third option does not make sense too. And, all in all, there is no prepositional phrases, which means that the length made the whole change :)

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hope this helps<3

do you have part b? ?

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