Answer:
The correct answer is letter "B": 2; 35.
Step-by-step explanation:
A company's Gross Domestic Product (GDP) represents its productivity over a certain period but the GDP per person or GDP per capita represents a country's productivity related to its number of inhabitants. Researches from the year 1870 until 2014 show that in the U.S. the GDP per capita at the beginning was around $4,300 and by 2014 it was almost $56,000.
The GDP per capita growth rate is 2% (1,8% exactly) which by the Pareto rule of 70/30, it implies:

Then, every 35 years the GDP per capita in the U.S. has grown 2% over the past decade (until 2014).