With half of west africa's population, which country experienced so much bad government that it went from an oil-rich, middle-income country to one of the world's poorest?
a. ghana

The answer of the question "With half of West africa's population, which country experienced so much bad government that it went from an oil-rich, middle-income country to one of the world's poorest?" is Niger. Niger's oil deposit was discovered around 1970s.

D.haka is the first answer and a.canberra is the second answer