The emergence of e-commerce as a new economic sector is a key change in the U.S. as the internet became popular. This led to significant transformations in retail and contributed to the growth of related industries. Overall, e-commerce highlights the profound impact of the internet on the economy. ;
The emergence of e-commerce as a new economic sector was a significant change in the U.S. as the internet became popular. This shift transformed traditional retail practices and created new economic opportunities. Therefore, the correct answer is A.
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