The three positions that nations occupy in the world system
a. core, periphery, and semi-periphery.
b. metropole, satellite, and semi-satellite.
c. state, nation-state, and nation.
d. wealth, power, and prestige.
e. bourgeoisie, middle class, and proletariat.

Option A

The three positions that nations occupy in the world system are core, periphery, and semi-periphery.

Explanation:

World system is a multidisciplinary method to social change and world history which is use stress the system of the world as a unit of social analysis. It is an international system that divide nations of the word according to their labor into core, periphery and semi -periphery. The core have high skill labor and high production cost compare to the others. The core countries dominate and use the periphery countries. The periphery countries also depend on the core countries for capital.

answer; polycythemia is the correct answer;

the missing space is phylum