A division of labor occurred when people started producing a surplus of food because it was no longer necessary to use all of the labor force to subsist off of agricultural goods. Once a society or community can produce enough to survive and eat the labor force will begin to work in other industries creating a division of labor this could include making textiles, building homes, or any other number of economic activities.
Answer:
A. it allowed brands to advertise and expand their markets.
Explanation:
The major impact of radio on the economy was that it brought advertising into American homes. ... It provided a source of entertainment which reached millions of American homes within three years. Although radio programs were entertaining, they had to be paid for; and this brought about the commercial.
The answer is assembly and speech