The correct answer should be b) of property damage and decreased worker productivity.
Many buildings were burned. In addition, people weren't working and without people the railroad can't earn money. That's why the correct answer is b.
During WW2, Japan had a one-party totalitarian military dictatorship under a semi-constitutional monarchy.
The modernization of US cities has caused a reduction in overall river pollution. The development of large farms has polluted the river through waste runoff. The use of the river for shipping has stayed relatively the same since 1800. The decrease in fishing in the river has led to a shortage of seafood products.
I think it would be China because it's the most developed country in Asia and is a very big impact on international trade.