Option B is the correct one. Sherry is Persuasive.
Sherry runs a business. She has good terms with vendors and the managers as well. It means she has a good relationship status within and outside of the company. So when it comes to having a deal with the vendors, she has a good negotiation edge with them in making the terms and conditions. So she is actually persuasive. She is influential. She has good relationship with both the parties, so she is acting as an influential person between the deal