Your mom is thinking of retiring. Her retirement plan will pay her either $250,000 immediately on retirement

Question:

Your mom is thinking of retiring. Her retirement plan will pay her either $250,000 immediately on retirement or $350,000 five years after the date of her retirement. Which alternative should she choose if the interest rate is
a. 0% per year?
b. 8% per year?
c. 20% per year?