6. Ron, David, and Mary formed Widget, Inc. Ron and David each received 40% of the stock, and Mary received the remaining 20%. Ron contributed land with an FMV of $70,000 and an adjusted basis of $20,000. The corporation also assumed a $30,000 liability on the property. David contributed land with an FMV of $30,000 and an adjusted basis of $15,000. David also contributed $10,000 in cash. Mary received her stock for services rendered. She normally would bill $20,000 for these services. What is Mary's basis in the corporate stock received? a. $0 b. $10,000 c. $15,000 d. $20,000