A Downward Sloping Demand Curve for Beef Means That

A downward sloping demand curve for beef means that:

A) as the price of beef rises, consumers substitute other meats for beef, and as the price of beef falls,consumers substitute beef for other goods.
B) as the price of beef rises, consumers buy more beef because they can afford less of other meats.
C) as the price of beef falls, consumers substitute other meats for beef.
D) as the price of chicken falls, consumers feel that the opportunity cost of consuming beef has increased.