Beef Is a Normal Good

Beef is a normal good. You observe that both the equilibrium price and quantity of beef have risen over time. Which of the following would be most consistent with this observation?

A) Consumers have experienced an increase in income and beef-production technology has improved.
B) The price of chicken has risen and the price of steak sauce has fallen.
C) Consumer tastes have changed so as to prefer beef less than before.
D) The demand curve for beef must be positively sloped.