How did the development of the Bessemer process affect the growth of cities?

How did the development of the Bessemer process affect the growth of cities?

a. It enabled the mass production of steel, which was used to build new factories.
b. It enabled the mass production of steel, which was used to build new universities.
c. It led to the invention of electricity, which supported expanding factories.
d. It led to the invention of the telegraph, which made business communications more efficient.