OPEC successfully raised the world price of oil in the 1970s and early 1980s, primarily due to:
a. an inelastic demand for oil and a reduction in the amount of oil supplied.
b. a reduction in the amount of oil supplied and a world-wide oil embargo.
c. a world-wide oil embargo and an elastic demand for oil.
d. a reduction in the amount of oil supplied and an elastic demand for oil.