Why there sentences are false?

A. If the price of gasoline decreases, it is expected that the demand curve for automobiles will shift towards

the left.

B. If the price of a substitute good for the one we are considering increases, the demand curve for the good

in question shifts to the left.

C. As production costs increase, the supply curve of a good shifts to the left.

D. If a minimum price is established below the equilibrium price, a surplus will appear.