Final answer:
A sole proprietorship pays taxes on the profits of the business at the owner's personal tax rate.
Step-by-step explanation:
A sole proprietorship pays taxes on the profits of the business at the owner's personal tax rate (option B).
As the sole proprietorship is not a separate entity from the owner, the profits of the business are treated as personal income for the owner and are subject to the owner's personal income tax rate.
This is different from corporations, which have separate tax rates and structures.