What Percentage of sub-Saharan Africa’s Economy is Accounted for by South Africa?

This is Not Yet Eaten #3, but today’s going to be a little different; the statistic is in the form of a question. The answer and the source of the question will be revealed tomorrow. In the mean time, try to guess the answer!

The 47 countries in sub-Saharan Africa have a total of 743 million inhabitants, about as many as the European Union and the United States combined. However, the region accounts for only a small part of the world economy. What percentage of sub-Saharan Africa’s economy is accounted for by one single country, South Africa?

A. 11 percent B. 18 percent C. 35 percent D. 62 percent