Question

Which of these was made possible by railroads?
O A. Faster mail delivery.
O B. Mass transportation.
O C. Changes to industry.
O D. All of the above are correct.​

Answer 1

Answer:

D

Explanation:

Although some of those came after others, they all were made better by railroads.

Answer 2

Answer:

D

Explanation:

THEY ALL ARE POSSIBLE BY RAILROADS