The supply curve for milk
选项：

A:shifts when the price of milk changes because the price of milk is measured on the vertical axis of the graph.;
B:shifts when the price of milk changes because the quantity supplied of milk is measured on the horizontal axis of the graph.;
C:does not shift when the price of milk changes because the price of milk is measured on the vertical axis of the graph.;
D:does not shift when the price of milk changes because the price of milk is measured on the horizontal axis of the graph.