Answer:
No, first is not a preposition.
Answer: Fears that hold you back are connected. By telling yourself that you can do anything you set your mind to and you can do it. We believe in you!
Explanation: Because when you are held back by fear you are being pulled away from your success.
Hey there!
C is the correct answer, as it properly uses commas to show unnecessary information through a prepositional phrase.
Hope this helped, have a good night!<span />