Answer:
Barack Obama, who won the presidential election in 2008 and was inaugurated in 2009.
Step-by-step explanation:
A sentence fragment is a group of phrases of a sentence but does not make or form a complete sentence. Sentence fragments, like the name, are just fragments of a sentence which may include dependent clauses and also have both subject and a verb in it. But they do not form or make a complete meaningful sentence.
In the given options, the example of a sentence fragment is the third option. In it, the phrase is "Barack Obama, who won the presidential election in 2008 and was inaugurated in 2009" contains just a part of the whole sentence, meaning it left off the sentence in between without any resolution or end sentence. This fragment contains just some bits of information about Obama and does not make a complete and meaningful sentence.