oops didnt mean to answer
Aksum's access to both the Red Sea and the Upper Nile enabled its strong navy to profit in trade between various African (Nubia), Arabian (Yemen), and Indian states. They traded with Roman traders as well as with Egyptian and Persian merchants. The empire was also rich with gold and iron deposits.
The correct answer is A.
During the late 1800's, America production was increasing greatly due to the development of interchangeable parts. Now that many businesses were able to mass produce goods, they needed buyers to consume them to ensure that the price of the goods did not decrease.
America wasn't worried about the spread of communism or the need for immigrant workers until the 20th century (hence why B and D are wrong).