Suppose the US government strengthens its environmental regulation on emissions of pollutant from motor vehicle's consumption of petroleum. Which of the following is true?

a.Exports of large size cars made by Japanese firms to the US will rise

b.Exports of small size cars made by Korean firms to the US will decrease

c.Exports of large size cars made by Japanese firms to the US will decrease

d.Exports of large size cars made by Germany firms to theUS will increase