Why did a provision of the interstate commerce act require railroads to make their rates public?

so that railroad employees did not have to remember the rates
so that railroad companies couldn’t unfairly charge different rates
so that railroads could operate more quickly and efficiently
so that different railroad companies would know what to charge

Option B, so that railroad companies couldn’t unfairly charge different rates is the right answer.  

Railroads during the 19th century became the main form of transportation for both men and goods. Therefore, the prices they charged and the methods they adopted had a direct influence on an individual. These Railroad companies had their pools over the area they serviced and that they had the power of prices fixing, excluding competitors, etc. In fact, the lack of competition sometimes led to an increase in the prices for their services.  

Therefore, The passing of the Interstate Commerce Act of 1887, was a response of the federal government to raising public attention. This Act provided Congress with a right to regulate private corporations involved in interstate dealings by challenging the philosophy of laissez-faire economics. Although, this act gave some authority to the Congress over interstate railroad rates but it did not enable the government to fix specific rates.

c)an idealized view of nature. hope this