Answer A is the correct one. The owner has personal responsibility for the company's liability.
There are many forms of business. Some important forms are Partnership, Corporation, Limited Liability Company, Sole Proprietorship etc.
Sole Proprietorship is a form of business in which the whole business is owned by a single person. He is the one liable for everything happening to the business. He is solely responsible for the liabilities and the profits as well. So this is usually a disadvantage of being a single owner, that you are the only one liable for all losses that may incur.