Answer:
A characteristic of ancient Ghana and Mali or Songhai that showed that it was an advanced civilization was the high investment in education and the construction of universities, schools and libraries.
Step-by-step explanation:
Ghana, Mali and Songhai were the three most important kingdoms in the African region and had a very advanced civilization in knowledge, arts, science and religion.
The three kingdoms invested heavily in the education of their population. Everyone had access to education at an early age and children were quickly taught to read. In addition, the construction of schools, universities and libraries was common, which was rare in ancient civilizations.