Answer:
The correct answer would be option A, Unconvincing.
Explanation:
When you are speaking or engaged in a discussion or argument or dialogue, or writing a document, you need to make sure that your words and sentences are persuasive enough to catch the attention of other people to whom you are addressing. So if you include just a part of a quotation to support your point, it will make your argument unconvincing. If you want to use the quotation, then you should use the full quotation in your argument. Any quotation or sentence said incomplete will be unconvincing for the audience.
