The positive of the railroads in the 1900s from your options is:
Products could be shipped faster than ever before.
Railroads significantly improved the speed and efficiency of transporting goods over long distances, which was a crucial development for trade and economic growth during that time. The other options are not accurate: while rail travel could be cost-effective, it wasn't necessarily the cheapest form of travel available, and trains were not designed to be loud to keep passengers awake.