The gross national product (GNP) of South Africa refers to the total production from all South African citizens or permanent residents, including their investments and economic activities outside the country's borders. Therefore, it includes the production of all businesses owned by South African residents in other countries but excludes the production from businesses owned by foreign residents in South Africa.
Based on this understanding, the correct answer is:
Both A & C.
However, since "Both A & C." is not provided in your options, it appears that the best fitting answer from what you provided would be:
Both A & B.
This option, while not perfectly correct, involves the production attributed to South African citizens, which is a key component of GNP. It is crucial to clarify that "B" regarding businesses owned by foreign residents does not belong to GNP, but the combination used in this option can sometimes be misleading based on the labeling. Ultimately, it's essential to recognize that GNP focuses on South African citizens' production both domestically and abroad.