B. Though Benjamin Franklin was known for his instrumental role in the founding of the United States.
This is a sentence fragment, you can tell because saying the sentence in your head or out loud feels incomplete, that is because the sentence wasn't finished, for example, "Though Benjamin Franklin was known for his instrumental role in the founding of the United States, he had many other accomplishments." Is a full sentence.
It’s an adjective because it’s describing it
1. No do not borrow because that is an item you want but don’t need
2. Yes would borrow because reliable transportation is something you need for work
3. No would not borrow because you do not need a brand new pair of shoes you seen
4. No would not borrow because you do not need a skateboard