Read the passage. (1) the labrador retriever is a very popular breed of dog. (2) the most popular purebred breed in the united states, in fact. (3) the second most popular breed is the yorkshire terrier. (4) though yorkies, as they are nicknamed, are small in size, they are big in popularity. which is the most effective way to correct the fragment in sentence (2)? add the missing subject. attach the fragment to sentence (3). add the missing verb. attach the fragment to sentence (1).

In my opinion, the best option would be D. Attach the fragment to sentence (1). We could attach this fragment to the sentence (1) by adding a dash between them. If we wanted to make a standalone sentence of this fragment, we would have to add both a subject and a verb to it (e.g. It is the most popular purebred breed in the United States, in fact). If we wanted to attach the fragment to the sentence (3), we would have to add a subject and a verb to it, and make a compound sentence, using a coordinator - as it would have two subjects and predicates (e.g. It is the most popular purebred breed in the United States, and/whereas/while the second most popular breed is the Yorkshire terrier.)