On July 1, of the current year, Robert forms the Yew Corporation. In exchange for 100 percent of the corporation's stock, Robert contributes land with a fair market value of $100,000. Robert acquired the land 5 years ago at a cost of $30,000. At the date of the contribution, the land is subject to a $10,000 mortgage which the corporation assumes. What is the basis of the land to Yew Corporation?

 a. $100,000 

b. $90,000

c. $30,000 O

d. $20,000 O

e. None of these 

choices are correct.