Mary Ann, age 65 retires from Bust it up corporation and receives 25000 shares of employer stock with a fair market value at the same time of $500,000. Mary Ann reported and paid ordinary income tax of $48,000 on the date of distribution of the stock. What is the net unrealized appreciation portion received by Mary at the time of distribution of employer stock?

a)48,000

b)348,000

c)452,000

d)500,000