Instructions: the Following Sentences Form a Paragraph

Multiple Choice

Instructions: The following sentences form a paragraph. For each set of choices, select the letter of the answer in which conjunctions or conjunctive adverbs are used correctly and punctuation is correct. Which sentences are correct?

A) The bike trail is one of the nicest places I know. It runs alongside the river so it takes riders through the most beautiful scenery you can find this close to the city.
B) The bike trail is one of the nicest places I know. Because it runs alongside the river, it takes riders through the most beautiful scenery you can find this close to the city.
C) The bike trail is one of the nicest places I know. It runs alongside the river, therefore it takes riders through the most beautiful scenery you can find this close to the city.