During the gilded age, how did companies build monopolies​

most people now work in jobs where they do one  kind  of work; they are carpenters, bankers, cooks, mechanics, and so forth. likewise, most  businesses produce  only certainkinds  of  goods  or  services, such as cars, tacos, or gardening  services. this feature of  production  is known as specialization.

i guess so you did not explain the answer clearly so i can't

1 wagon is the right answer