In General,supply Curves Slope Upward to the Right Because

In general,supply curves slope upward to the right because

A) increases in the price of a commodity lead to rightward shifts of the supply curve.
B) rising prices motivate producers to offer more units for sale.
C) technology progresses over time, increasing the ability of firms to produce more at existing prices.
D) of increases in input prices as production is increased.
E) empirical studies almost always show that this is the case.