The answer is C: The shareholders are not required to be U.S. citizens.
Explanation for each option:
A. The business cannot be a subsidiary of another corporation - This is correct. To qualify as a subchapter S corporation, the business must be an independent entity and cannot be a subsidiary of another corporation.
B. The shareholders must be U.S. citizens - This is correct. Shareholders of a subchapter S corporation must generally be U.S. citizens or residents.
C. The shareholders are not required to be U.S. citizens - This is incorrect. As mentioned, shareholders must be U.S. citizens or residents, making this statement false.
D. Partnerships and C corporations may not own shares in a subchapter S corporation - This is correct. Only individuals, certain trusts, and estates are allowed to be shareholders in a subchapter S corporation.
E. The business can have only one class of stock issued and outstanding - This is correct. A subchapter S corporation can only have one class of stock, although differences in voting rights are allowed.