Siberia had experienced many environmental problems because of

The choices can be found elsewhere and as follows:
difficulties transporting goodsfighting during World War IIprivatization of industrypolicies during the Soviet era
I believe the correct answer is the last option. Siberia has experienced many environmental problems because of policies during the Soviet era. 

You not be doing this in a quiz. if you actually studied your work you would know the answer. the answer though is that they would use gdp per capita because it measures a smaller portion (person). this could show individual growth per person in the country.