Belgium, Hungary, Sweden, and Germany Are All Members of the EU

Belgium, Hungary, Sweden, and Germany are all members of the EU. Which of the following statements is an accurate description of trade between these nations?

A) Belgium and Germany are permitted to engage in free trade due to their proximity to each other, however, Sweden only has free trade with Finland, and Hungary only has free trade with Switzerland, Austria, and Croatia.
B) The EU has abolished customs duties at internal borders for these and other member nations and put in place a uniform system for taxing imports. Internal border controls subsequently disappeared.
C) Customs officers that collect tariffs are now found at the internal borders of all EU member nations.
D) Belgium, Hungary, Sweden, and Germany are four nations strongly considering abandoning the EU common market. The global trading bloc has proved inefficient in these nations' attracting global business.