Refer to the Following Figure

Refer to the following figure. According to the figure,the movement from point (4,3) to point A is a function of ____________,while the subsequent movement from point A to point (2,3) results from ____________.

A) an increase in the price of pizza; a decrease in the price of Pepsi
B) a decrease in the price of pizza; an increase in the price of Pepsi
C) a combination of the substitution and real-income effects; a decrease in the price of pizza
D) the substitution effect alone; the real-income effect alone
E) the real-income effect alone; the substitution effect alone