Marcus purchased Vinnie and Marie’s personal residence for $225,000 cash and the assumption of their $100,000 mortgage. Vinnie and Marie bought the house six years ago for $275,000 and have used it as a primary residence. What amount of gain should Vinnie and Marie recognize on the sale of their personal residence?

a. $0.

b. $50,000.

c. $100,000.

d. $225,000.