.Using 2010 as the base year, the gross domestic product (GDP) deflator in 2011 was 97. Which of the following must be true?
A The inflation rate in 2011 was positive.
B. The inflation rate in 2011 was negative.
C. The inflation rate in 2011 was zero.
D. The purchasing power of a dollar decreased by 3 percent.
E. The real output increased by 3 percent.