In sept 2010, bill and Linda, a married couple with 50000 of gross income, cashed qualified Series EE US savings bonds which they had purchased in 2004. The proceeds were used to help pay for their son's college tuition. They received gross proceeds of 3500 representing 3000 pricing and 500 of interest. The qualified higher education expenses they paid in 2010 totaled 2100. Their modified adjusted gross income for the year was 55000. How much of the 500 interes can bill and Linda exclude from gross income in 2010?
A 0
B 200
C 300
D 500