On July 1, 2010, Riley exchanged investment real property, with an adjusted basis of $160,000 and subject to a mortgage of $70,000, and received from Wilson $30,000 cash and other investment real property having a fair market value of $250,000. Wilson assumed the mortgage. What is Riley's recognized gain in 2010 on the exchange?
a) $ 30,000
b) $ 70,000
c) $ 90,000
d) $100,000
Answer: d) $100,000