Agriculture, Tourism, Entrainment, Solid minerals like Gold, Copper, Silver Etc.
It doesn't matter if it's oil or precious metals. A country that builds it's economy over mining precious metals or drilling for oil/gas is considered underdeveloped. Countries with an economy focused towards agriculture are also considered underdeveloped. Tourism in Nigeria? Really?
The only solution is building a modern industry with production facilities. I'm pretty skeptical about the process of industrialization in Africa.
Not enough engineers, no infrastructure, no corporate culture and strong work ethics. I don't think that any industrialization in Nigeria is going to happen anytime soon.
Diversifixation? Is this a new word or something? You mean diversification, right? Or maybe you mean something between diversification and fixation?