This was the dominant religion in sub-saharan africa prior to the colonial period. christianity hindu indigenous islam

The right answer "Indigenous"

North Africa has a Muslim majority for several centuries, yet sub-Saharan Africa has experienced a dramatic religious shift in the 20th century. In 1900, Christians (9%) and Muslims (14%) were a minority in sub-Saharan Africa, while 76% of the population followed African indigenous religions. Many of these religions were brought to the Americas through the slave trade and gave birth to African-American religions, such as candomblé and umbanda in Brazil, santeria in Cuba and voodoo in Haiti.

this doesn't support enough information to answer the question.

for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.