The most important element in south africa's economic expansion was

Population of this city. also, look for information on available public transit, bike-sharing, and other commuting options. use the information you find and write about it promoting alternative transportation

The us is first  the  u.s. economy  remains the  largest in the world  in terms of nominal  gdp. however, the  u.s. economy  loses its spot as the number one  economy  to china when  measured  in terms of  gdp  based on ppp. in these terms, china's  gdp  is $23.19 trillion exceeds the  u.s. gdp  of $19.42 trillion

Ithink this answer here is a or d

Ithink its the 3rd one