In a Small, Agricultural Nation, Consumers Buy Only Steak and Potatoes

In a small, agricultural nation, consumers buy only steak and potatoes. In 2009, the base year, the typical consumer spent $potatoes on strawberries and $100 on steak. The price of potatoes is $1 and the price of steak is $2 in 2009. In 2009, the price of potatoes is $2 and the price of steak is $1. The CPI for 2010 is

A) 25 percent.
B) 100.
C) 110.
D) 80.
E) 125.