The Price of a First-Class Stamp in 1957 Was 3

The price of a first-class stamp in 1957 was 3 cents, and it is 49 cents in 2014. From this we know that

A) both the relative and the absolute price of first-class stamps increased from 1957 to 2014.
B) the money price of first-class stamps increased from 1957 to 2014 but the absolute price of first-class stamps stayed constant.
C) the money price of first-class stamps increased from 1957 to 2014 and the relative price of first-class stamps decreased.
D) the money price of first-class stamps increased from 1957 to 2014, but we can't tell if the relative price of first-class stamps increased or decreased without more information.