Final answer:
In Siberia, the Soviet Union's central planners chose to build industrial complexes at sites where rivers and railroads intersected. This allowed for efficient transportation of resources and goods.
Step-by-step explanation:
In Siberia, Soviet central planners tended to situate industrial complexes at sites where two natural and human-made features intersected. The correct pair of one natural and one human-made landscape feature that they used were rivers and railroads. This allowed for easy transportation of resources and goods to and from the factories. By utilizing the rivers and railroads, the Soviet Union was able to efficiently develop their industrial sector in Siberia.