Answer:
The correct answer is B. The river labeled with the number 1 on the map above is the Volga River.
Step-by-step explanation:
The Volga is a river of European Russia that, with its 3645 km, is the longest in Europe and the 15th longest in the world.
The Volga rises in the Valdai Hills, between Moscow and St. Petersburg, and empties into the Caspian Sea. It is navigable in almost all its route thanks to the enormous works of conditioning realized mainly during second half of the 20th century. Its hydrographic basin, with an area of 1 350 000 km², is the 18th largest in the world and irrigates a third of European Russia, gathering a large mosaic of villages and, since World War II, an important part of the industrial activities of Russia.