Deflation Is Best Described As

Deflation is best described as:

A) when all prices in the economy fall.
B) when the prices of some goods rise and prices of some goods fall, but more goods have price increases than decreases.
C) when the prices of some goods rise and prices of some goods fall, but fewer goods have price increases than decreases.
D) when the overall level of prices of goods falls.
E) when the overall level of prices of goods rises.