In This Year,Country a Has a Real GDP Per Person

In this year,Country A has a real GDP per person that is 4 times greater than that of Country B.Country B's growth rate of real GDP per person is 3.5 per cent per year.How many years will it take for Country B's real GDP per person to reach the same level that Country A had in this year?

A) 60 years
B) 40 years
C) 10 years
D) 20 years
E) 56 years