I'm having trouble using a financial function in excel for this problem:

8. Tom wants to buy a new house. The monthly mortgage payment is $1,200, the annual interest rate is 4.26% and the term is 30 years. After 30 year's payments, he still needs to pay $680,000 to get the title of the house at the end of the 30th year, how much is this house worth to Tom today?

a. $536,528.65

b. $692,683.45

c. $122,432.30

d. $433,515.30