Gerald received a 1/3 capital and profits limited partnership interest in the XYZ limited partnership. In exchange for this interest, Gerald contributed a building with a fair market value of $30,000 with an adjusted basis to Gerald of $ 15,000. It was encumbered by a $ 9,000 nonrecourse debt that the general partners of XYZ personally assumed. What is Gerald's basis in his partnership interest immediately after this contribution?

Which is right ?

$6,000

$ 9,000

$ 21,000

$ 24,0000