Question

which statement describes how electricity affected industry in the early 1900s?
electricity was so costly to use that it drove up prices.
factories used electricity to power their machines and produce more goods.
electricity was seldom used because coal was so cheap.
factories tried to use electricity for their machines, but it proved too dangerous.

Explanation:

In the early 1900s, electricity became a crucial power source. Factories adopted it to run machines. This led to increased production capacity as electrical - powered machinery was more efficient than previous power sources (like steam - powered from coal in some cases). The cost of electricity was not prohibitively high to drive up prices significantly in the long - run for industrial use. Also, electricity was not seldom used as it offered advantages over coal in terms of ease of distribution and more precise power application in factories. And while there were initial concerns about safety, it was not "too dangerous" to be used in factories.

Answer:

Factories used electricity to power their machines and produce more goods.