What is a shareholder's basis in S corporation stock received for services rendered?

A. The average fair market value of the S corporation's stock during the time that the services were rendered.

B. The fair market value of the S corporation's stock at the time of transfer.

C. The fair market value of the services rendered, as determined by the Bureau of Labor Statistics.

D. The value of the services rendered, as determined by what the shareholder normally charges.