If A and B are substitutes and the price of A rises, we will observe:

a) a decrease in the equilibrium price and the equilibrium quantity of B.
b) an increase in the equilibrium price and the equilibrium quantity of B.
c) a decrease in equilibrium price but an increase in the equilibrium quantity of B.
d) an increase in the equilibrium price but a decrease in the equilibrium quantity of B.
e) none of the above.

Ans: b) an increase in the equilibrium price and the equilibrium quantity of B.