Skateboards International of Regina, Saskatchewan, Was Able to Sell 20

Skateboards International of Regina, Saskatchewan, was able to sell 20 000 skateboards at a price of $60 in 2010. In 2011, it was able to sell only 12 000 of the same skateboards at a price of $60. What has Skateboards International evidently experienced?

A) an increase in quantity supplied
B) a decrease in demand
C) an increase in demand
D) an increase in supply