The qualified business income deduction is unavailable to which of the following businesses: 

a. A sole proprietor dental practice that generates about $70,000 in income each year.

b. An incorporated small tools manufacturer.

c. A partnership operated by a husband and wife that sells wood carvings over the Internet.

d. A S corporation that owns and operates a restaurant. The S corporation has six different owners. 

e. The QBI deduction is available to all of the above.