Gross capital formation in Nigeria 1964-1973, what can be inferred from the histogram above?

• A.there was a steady growth of capital formation in the period
• B.capital formation in the last two years exactly equalled those of all previous years combined
• C.at the end of the period, Nigeria had become self-sufficient
• D.Nigeria experienced serious economic problems during the period
• E.Nigeria is one of the richest countries in Africa